Botox (onabotulinumtoxinA)

Botox generic or biosimilar

Botox is a biologic drug that’s available only as a brand-name medication. It’s not currently available in generic or biosimilar form.

Biologic medications are made from living cells, so it’s not possible to copy these drugs exactly. A generic, on the other hand, refers to drugs made from chemicals. A generic is an exact copy of the active drug in a brand-name medication.

Biosimilar medications are considered just as safe and effective as their parent drug. And as with generics, biosimilars tend to cost less than brand-name medications.

Botox for chronic migraine

The Food and Drug Administration (FDA) approves prescription drugs such as Botox to treat certain conditions. Botox is approved to help prevent headaches in adults with chronic migraine. In addition, the drug is approved to treat other conditions, which are described in the “Other uses for Botox” section below.

What is migraine?

Migraine is a neurologic condition that can cause severe, throbbing, disabling headaches. The headaches typically occur on one side of the head and last for several hours. Sometimes, the headaches can last for days.

With migraine headaches, you’ll usually also have nausea and increased sensitivity to light or sound. Some people also have a sensory aura before or during the headache. Sensory auras may involve changes in your vision, such as having blind spots or seeing light flashes or zigzag lines. With migraine, it’s also possible to experience tingling or buzzing sensations and to have difficulty speaking.

Migraine is considered to be chronic if you have headaches that last at least 4 hours on 15 or more days each month.

Botox is used in chronic migraine management to help prevent headaches and other symptoms. The drug works by stopping certain nerves in your body from sending signals. The nerves affected by Botox are those involved in causing migraine symptoms and producing pain during a migraine headache.

Note: Botox is not used to help prevent symptoms of episodic migraine, which occurs on 14 or fewer days per month.

What to expect with Botox for migraine

For migraine management, you’ll typically receive Botox injections once every 3 months. During your injection visits, your doctor will give you multiple injections of the drug. They’ll typically inject Botox into muscles in the following areas:

• your forehead
• the area around your temples
• the back of your neck

Botox can help reduce the number of migraine attacks you have and how long they last. But the drug won’t completely stop your migraine headaches. In addition, Botox doesn’t work right away, and it doesn’t work for everyone.

Some people start to experience an improvement in their migraine headaches just 2–4 weeks after their first set of Botox injections. But it can take two sets of injections and up to 6 months of treatment before you get the maximum effect from Botox.

You can see this article about Botox for migraine for more details about how the drug treats this condition. You can also see our headache and migraine hub for more articles and resources about this condition.

Effectiveness for chronic migraine

In two clinical trials, Botox was effective in preventing migraine headaches in adults. For details of these clinical trials, see the Botox prescribing information.

Botox and children with chronic migraine

Botox isn’t approved for use in children with chronic migraine. It’s only approved for use in adults ages 18 years and older with this condition.

One clinical trial looked at children and adolescents who were younger than 18 years of age with chronic migraine. The trial didn’t find Botox to be effective in preventing migraine headaches in this age group.

Other uses for Botox

The Food and Drug Administration (FDA) approves prescription drugs such as Botox to treat certain conditions. Botox may also be prescribed off-label for other conditions. Off-label use is when a drug that’s approved to treat one condition is prescribed to treat a different condition.

In addition to chronic migraine in adults (see the previous section), Botox is approved to treat the following in certain situations:

• overactive bladder (OAB) in adults with urinary incontinence (involuntary leaking of urine), urgency, and frequency
• urinary incontinence caused by a nerve disorder, such as multiple sclerosis (MS) or spinal cord injury, in adults and children ages 5 years and older
• upper or lower limb spasticity (involuntary muscle contractions) in adults and children ages 2 years and older
• cervical dystonia (involuntary muscle spasms in the neck) in adults
• blepharospasm (uncontrollable blinking) related to dystonia (involuntary muscle spasms) in adults and children ages 12 years and older
• strabismus (crossed eyes or misaligned eyes) in adults and children ages 12 years and older
• severe axillary hyperhidrosis (excessive underarm sweating) in adults

The use of Botox for treating these conditions is described in detail below.

Botox for overactive bladder

Botox is FDA-approved to treat overactive bladder (OAB) in adults with the following urinary symptoms:

• urinary incontinence (involuntary leaking of urine)
• urgency
• frequency

OAB is caused by uncontrollable spasms of a muscle in your bladder wall. This muscle is called the detrusor muscle. When the detrusor muscle contracts, it squeezes your bladder. With OAB, detrusor muscle spasms cause you to have sudden and frequent urges to urinate. And these urges can sometimes lead to incontinence if you can’t get to a toilet quickly enough.

Botox is used to treat OAB when drugs called anticholinergics either caused bothersome or severe side effects, or didn’t work well enough. Examples of anticholinergic drugs used for OAB include oxybutynin and tolterodine (Detrol).

Botox can help reduce the number of urinary incontinence episodes you have. And the drug can also decrease the number of times per day that you need to urinate.

To treat OAB, Botox is injected directly into the detrusor muscle in your bladder. The drug works by stopping nerves from sending signals that cause this muscle to contract. These injections are given through a thin tube called a cystoscope that’s inserted into your bladder.

The effect of Botox injections for OAB lasts at least 12 weeks. After that point, the drug’s effect starts to wear off and repeat treatment may be needed. However, in clinical trials, the drug’s effect lasted for an average of 24 weeks before repeat treatment was needed.

You can see this article about Botox for OAB for more details about how the drug treats this condition.

Effectiveness for overactive bladder

In two clinical trials, Botox was effective in treating OAB in adults. For details about these trials, see the Botox prescribing information.

Botox for urinary incontinence caused by a nerve disorder

Botox is FDA-approved to treat urinary incontinence caused by a neurologic condition (nerve disorder). Examples of these nerve disorders include multiple sclerosis (MS) and spinal cord injury. For this condition, Botox can be used in adults and children ages 5 years and older.

With urinary incontinence, you have involuntary leaking of urine. This is a common problem in people with certain nerve disorders. The incontinence happens because nerves that aren’t functioning correctly send inappropriate signals to the muscle in your bladder wall. This muscle is called the detrusor muscle. The inappropriate signals make your detrusor muscle contract uncontrollably. And this squeezes your bladder and causes urinary incontinence.

Botox is used for this condition when drugs called anticholinergics either caused bothersome or severe side effects, or they didn’t work well enough. Examples of anticholinergic drugs used for this purpose include oxybutynin and tolterodine (Detrol).

To treat this type of urinary incontinence, Botox is injected directly into the detrusor muscle in your bladder. The drug works by stopping nerves from sending signals that cause this muscle to contract. These injections are given through a thin tube called a cystoscope that’s inserted into your bladder.

Effectiveness for urinary incontinence caused by a nerve disorder

In two clinical trials, Botox was effective in treating urinary incontinence caused by a nerve disorder in adults. For details about these trials, see the Botox prescribing information.

A separate clinical trial found Botox to be safe and effective for treating nerve-related urinary incontinence in children ages 5 years and older.

Botox for upper and lower limb spasticity

Botox is FDA-approved to treat certain types of muscle spasticity in adults and children ages 2 years and older. With this condition, your muscles contract involuntarily and become stiff. Upper and lower limb spasticity can cause stiffness in your elbows, hands, fingers, ankles, or toes. Muscle spasticity can be painful, and it can make it difficult for you to do daily activities.

Upper or lower limb spasticity may occur after someone has a stroke.

But limb spasticity may also be caused by nerve disorders, such as multiple sclerosis (MS) and cerebral palsy. Brain or spinal cord injury can also result in limb spasticity. All these conditions can damage nerves in your brain, causing them to malfunction and result in limb spasticity.

To treat limb spasticity, Botox is injected into certain muscles in the affected arm, hand, or leg. The drug works by stopping nerves from sending signals that are causing the muscle spasticity. This action of Botox allows the muscles to relax.

The effect of Botox injections for limb spasticity typically lasts about 12 weeks. After that point, the drug’s effect wears off and repeat treatment may be needed.

Effectiveness for upper and lower limb spasticity

In several clinical trials, Botox was effective in treating limb spasticity in adults and children ages 5 years and older. For details about these trials, see the Botox prescribing information.

Botox for cervical dystonia

Botox is FDA-approved to treat cervical dystonia, which is also called spasmodic torticollis. For this purpose, Botox can be used in adults.

With cervical dystonia, you have involuntary muscle spasms in your neck. The spasms cause repetitive, uncomfortable, twisting movements in your head or neck. These movements place your head in an atypical position and cause pain in your neck.

To treat cervical dystonia, Botox is injected into the affected muscles in your neck or upper back. The drug works by stopping nerves from sending the signals that cause those muscles to contract. This allows the muscles to relax.

The effect of Botox injections for this condition typically lasts about 12 weeks. After that, the effect wears off and repeat treatment may be needed.

You can see this article about Botox for cervical dystonia for more details about how the drug treats this condition.

Effectiveness for cervical dystonia

In a clinical trial, Botox was effective in treating cervical dystonia in adults. For details about this clinical trial, see the Botox prescribing information.

Botox for blepharospasm

Botox is FDA-approved to treat blepharospasm (uncontrollable blinking) related to dystonia (involuntary muscle spasms). The drug is approved for this use in adults and children ages 12 years and older.

Dystonia describes a range of movement disorders that are caused by problems with nerve messages sent to your muscles. This condition can affect one or many parts of your body.

With blepharospasm, you have muscle spasms in your eyelids. These spasms cause excessive and uncontrollable blinking of both eyes. In severe cases of blepharospasm, you may not be able to open your eyes for several minutes at a time. The condition can irritate your eyes, and it can make them more sensitive to light. Our eye health hub may have more information about this condition.

To treat blepharospasm, Botox is injected into the affected muscles in your upper and lower eyelids. The drug works by stopping nerves from sending the signals that are causing those muscles to contract. This weakens the muscles and stops them from causing excessive blinking.

For blepharospasm, Botox’s effect typically lasts about 12 weeks before it wears off. At that time, repeat treatment can be done if needed.

Effectiveness for blepharospasm

In clinical trials, Botox was effective in treating blepharospasm. The majority of people given Botox for this condition had improvement after treatment.

Botox for strabismus

Botox is FDA-approved to treat strabismus in adults and children ages 12 years and older.

Strabismus affects one or more of the muscles on the outside of one eyeball. It causes the affected muscles to contract more strongly than other muscles. This causes the eyeball to turn, so that your eyes are crossed or misaligned and don’t look in the same direction.

To treat strabismus, Botox is injected into the muscles that are pulling your eyeball in the wrong direction. The drug works by stopping nerves from sending signals that are causing the muscles to contract and pull your eyeball. You can visit our eye health hub for more information about this condition.

Botox’s effect for this condition typically lasts about 12 weeks before it wears off. At that time, repeat treatment may be needed.

Effectiveness for strabismus

In a clinical trial, Botox was effective in treating strabismus in people who were given one or more injections of the drug. For details about this trial, see the Botox prescribing information.

Botox for severe axillary hyperhidrosis

Botox is FDA-approved for use in adults with severe primary axillary hyperhidrosis (excessive underarm sweating). Botox can be used to treat this condition when antiperspirants applied to the underarms don’t work well enough to manage sweating.

With hyperhidrosis, you sweat excessively. The sweating can cause discomfort and anxiety. And it can lead to problems with your emotional well-being, relationships, social life, and daily activities.

With primary axillary hyperhidrosis, there’s no apparent cause for the excessive sweating, such as an underlying health condition.

To treat severe primary axillary hyperhidrosis, Botox injections are given into the skin in your armpits. The drug works by stopping nerves from sending signals that activate the sweat glands in that area.

If needed, Botox injections can be repeated after symptoms return. For this purpose, repeat Botox treatment is typically done at least 8 weeks after the first injection.

You can see this article about Botox for excessive sweating for more details about how the drug treats this condition.

Note: Botox is only used for hyperhidrosis in the axillary (underarm) area. Botox’s safety and effectiveness for hyperhidrosis in other body areas isn’t known.

Effectiveness for severe axillary hyperhidrosis

In two clinical trials, Botox was effective in treating axillary hyperhidrosis in adults. For details about these trials, see the Botox prescribing information.

Botox and children

Botox is FDA-approved to treat the following conditions in children:

• urinary incontinence (involuntary leaking of urine) caused by a nerve disorder in children ages 5 years and older
• upper or lower limb spasticity (involuntary muscle contraction) in children ages 2 years and older
• blepharospasm (uncontrollable blinking) related to dystonia (involuntary muscle spasms) in children ages 12 years and older
• strabismus (crossed eyes or misaligned eyes) in children ages 12 years and older

To read more about these uses of Botox and its effectiveness in treating them, see the sections above for each condition.

Off-label uses for Botox

In addition to the uses listed above, Botox may be prescribed off-label for other purposes. Off-label drug use is when a drug that’s FDA-approved for one or more uses is prescribed for a different one that’s not approved. Below are examples of off-label uses for Botox.

Botox for tension headaches

Botox isn’t FDA-approved to treat tension headaches. However, sometimes it’s prescribed off-label to help prevent chronic tension headaches.

Tension headaches are also called stress headaches. They tend to affect both sides of your head. And they may occur along with stiffness in your neck or shoulders. Unlike migraine headaches, tension headaches don’t typically cause nausea. However, people with tension headaches may be more sensitive to light and sound.

With chronic tension headaches, you have tension headaches on at least 15 days each month, for at least 3 months in a row.

Botox is very effective in preventing chronic migraine headaches. So it’s not surprising that the drug has also been studied for preventing chronic tension headaches. A 2019 review of research suggests that Botox could be effective for this purpose. However, more research is needed to know if the treatment is effective for this use.

If you have tension headaches, talk with your doctor. They can determine possible causes of your headaches and suggest appropriate treatment options.

Botox for anal fissures

Botox isn’t FDA-approved to treat anal fissures. However, the drug is sometimes prescribed off-label for this condition.

An anal fissure is a tear or crack in the tissue that lines your anus. These fissures cause pain and bleeding during and after bowel movements.

Muscle spasms in the anal sphincter (ring of muscles around your anus) may be associated with causing anal fissures. The muscle spasms may also prevent anal fissures from healing. So anal fissures are typically treated with medications that help to relax the anal sphincter.

A 2016 review of the causes and treatments of anal fissures suggests that Botox may be an effective treatment option. According to this review, injecting Botox into a certain area of the anal sphincter can result in most fissures healing. However, in some cases, the fissures may come back.

If you’re interested in receiving Botox to treat an anal fissure, talk with your doctor. They can recommend appropriate treatment options for your condition.

Botox for depression

Botox isn’t FDA-approved to treat depression. However, there’s a growing amount of research that suggests Botox may be effective for treating this condition.

For example, a 2020 review looked at five studies of Botox for depression. These studies showed that Botox may be effective in treating depression. However, more studies are needed to confirm the drug’s effectiveness in treating this condition.

If you’re interested in trying Botox to treat depression, talk with your doctor. They can recommend appropriate treatment options for your condition.

Botox side effects

Botox can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Botox. These lists don’t include all possible side effects.

For more information on the possible side effects of Botox, you can refer to this article. You can also talk with your doctor or pharmacist. They can give you tips on how to manage any side effects that may be bothersome.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you would like to report to the FDA a side effect you’ve had with Botox, you can do so through MedWatch.

Mild side effects

Mild side effects of Botox can include:*

• pain, tenderness, discoloration, swelling, bruising, bleeding, or infection at Botox injection sites
• unwanted muscle weakness near Botox injection sites
• nausea
• fever
• achy muscles
• upper respiratory tract infections, such as the common cold
• headache
• neck pain
• drooping eyelids
• dry eyes
• dry mouth
• painful urination and urinary tract infection (UTI) in people receiving Botox for urinary incontinence (involuntary leaking of urine)

Most of these side effects may go away within a few days or a couple of weeks. But if they become more severe or don’t go away, talk with your doctor or pharmacist.

* This is a partial list of mild side effects from Botox. Side effects may vary depending on the condition treated. To learn about other mild side effects, talk with your doctor or pharmacist, or visit Botox’s prescribing information.

Serious side effects

Serious side effects from Botox aren’t common, but they can occur. Contact your doctor right away if you have serious side effects. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

• Corneal ulceration (open sore on the clear covering over the front of the eye) due to reduced blinking in people receiving Botox to treat blepharospasm. Symptoms can include:
  • eye pain and redness
  • blurred vision
  • watery eye
  • feeling that something is in your eye
  • white spot on the cornea
• Urinary retention (inability to empty your bladder) in people receiving Botox to treat urinary incontinence. Symptoms can include:
  • burning sensation when urinating
  • difficulty urinating
  • frequently feeling like you need to urinate
• Retrobulbar hemorrhage (bleeding behind the eye) in people receiving Botox to treat strabismus. Symptoms can include:
  • eye pain
  • decrease in or loss of vision
  • black eye
  • proptosis (bulging eyeball)
• Autonomic dysreflexia (a serious complication of the central nervous system) in people receiving Botox to treat urinary incontinence due to a neurological condition. Symptoms can include:
  • very high blood pressure
  • severe headache
  • sweating
  • seizure
  • stroke
• Allergic reaction.*
• Spread of toxin effects, which may lead to difficulty breathing or swallowing that may be life threatening.*†

* This serious side effect is explained in more detail below in “Side effect details.”
† Botox has a boxed warning about this risk. A boxed warning is the most serious warning from the FDA. A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Side effects in children

Botox is approved for use in children with certain conditions. Below, we list these conditions and briefly describe the side effects seen in children who have them.

• Urinary incontinence (involuntary leaking of urine) caused by a nerve disorder: Side effects of Botox in children with urinary incontinence were similar to side effects in adults treated for this condition.
• Upper and lower limb spasticity (involuntary muscle contraction): The most common side effect in children with these conditions is upper respiratory tract infection, such as the common cold. This side effect occurs more often in children with these conditions than it does in adults.
• Blepharospasm (uncontrollable blinking) and strabismus (crossed eyes): Side effects of Botox in children with these conditions are similar to side effects in adults treated for these conditions.

Side effect details

You may wonder how often certain side effects occur with this drug. Below are some details on several of the side effects this drug may cause.

Spread of toxin effects

In some cases, Botox’s effects may spread away from the site where it’s injected. This can cause a serious condition called botulism, which is described further below.

In fact, Botox has a boxed warning about the risk of toxin effects spreading. A boxed warning is the most serious warning from the FDA. It alerts doctors and patients about drug effects that may be dangerous.

Symptoms caused by botulism

Botulism may lead to symptoms such as:

• low energy
• muscle weakness all over your body
• drooping eyelids
• double vision
• loss of bladder control
• hoarse voice
• difficulty speaking
• difficulty breathing
• difficulty swallowing

Symptoms of botulism can occur hours, days, or weeks after you’ve had a Botox injection. But it’s not known for sure how often the symptoms occur in people using this drug. Be sure to tell your doctor if you develop any symptoms of botulism, even if they do not occur right after you receive a Botox injection.

People with the highest risk of botulism symptoms from Botox are children who are treated for spasticity. Serious effects caused by the spread of toxin effects haven’t been reported in people given recommended doses of Botox for certain other conditions. These conditions are chronic migraine, excessive sweating, blepharospasm (uncontrollable blinking), and strabismus (crossed eyes or misaligned eyes).

What to do for symptoms caused by botulism

It’s important to note that breathing and swallowing problems caused by Botox can be life threatening. The risk of these problems is higher in people who already have breathing or swallowing problems.

If you have any difficulty with breathing, swallowing, or speaking after having Botox injections, contact your doctor right away. But if your symptoms feel life threatening, call 911 or your local emergency number.

In addition, if you have loss of strength, muscle weakness, blurred vision, dizziness, or drooping eyelids, you should avoid driving. And let your doctor know about these symptoms right away.

Pain after injection

You may have some pain after receiving a Botox injection. In fact, it’s common to have pain, tenderness, swelling, or bruising in areas where the drug is injected. In clinical trials, some people who received Botox had injection site pain.

In these trials, there were reports of other types of pain occurring. For example, some people who received Botox for migraine experienced:

• headache
• neck pain
• muscle pain
• musculoskeletal pain, such as shoulder pain
• jaw pain

If you have pain of any kind after receiving a Botox injection, talk with your doctor. They can recommend how to best manage your discomfort.

Allergic reaction

As with most drugs, some people can have an allergic reaction after receiving Botox. Allergic reaction occurred during the drug’s clinical trials, but it’s not known how often it occurred.

Symptoms of a mild allergic reaction can include:

• skin rash
• itchiness
• flushing

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:

• swelling under your skin, typically in your eyelids, lips, hands, or feet
• swelling of your tongue, mouth, or throat
• difficulty breathing

Contact your doctor right away if you have a severe allergic reaction to Botox. But call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.

Hair loss

You may have hair loss after receiving Botox, but this side effect isn’t very common. In fact, hair loss wasn’t reported during clinical trials of Botox.

However, a few cases of hair loss have been reported since Botox was approved for use and became available on the market. But it’s not known how often these cases of hair loss occurred. And it’s not known whether the hair loss was caused by Botox.

If you’re concerned about hair loss with Botox, talk with your doctor.

Botox cost

As with all medications, the cost of Botox can vary. The actual price you’ll pay depends on your insurance plan, your location, and what condition you’re taking the drug for.

You won’t pick up Botox from a pharmacy. You’ll receive Botox injections from a healthcare professional. To find out how much Botox treatment will likely cost, talk with your doctor or their office staff.

Your insurance company may require you to get prior authorization before approving coverage for Botox. This means that your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the prior authorization request and decide whether the drug will be covered.

If you’re not sure whether you’ll need to get prior authorization for Botox, contact your insurance plan.

If you have Medicare, this article about Medicare coverage for Botox may be helpful.

Financial and insurance assistance

If you need financial support to pay for Botox, or if you need help understanding your insurance coverage, help is available.

A Botox Savings Program is available, and it may help lower the cost of your treatment. For more information and to find out if you’re eligible for support, call 800-44-BOTOX (800-442-6869) or visit the program website.

Generic or biosimilar version

Botox is available only as a brand-name medication. It’s not currently available in biosimilar form.

Biologic medications are made from living cells, so it’s not possible to copy these drugs exactly. Generics, on the other hand, are drugs made from chemicals. A generic is an exact copy of the active drug in a brand-name medication.

Biosimilar medications are considered just as safe and effective as their parent drug. And as with generics, biosimilars tend to cost less than brand-name medications.

How Botox works

Botox is used to manage several different conditions. Specifically, Botox is FDA-approved for the following uses:

• preventing headaches in adults with chronic migraine
• treating overactive bladder (OAB) in adults with urinary incontinence (involuntary leaking of urine), urgency, and frequency
• treating urinary incontinence caused by a nerve disorder, such as multiple sclerosis (MS) or spinal cord injury, in adults and children ages 5 years and older
• treating upper or lower limb spasticity (involuntary muscle contractions) in adults and children ages 2 years and older
• treating cervical dystonia (involuntary muscle spasms in the neck) in adults
• treating blepharospasm (uncontrollable blinking) related to dystonia (involuntary muscle spasms) in adults and children ages 12 years and older
• treating strabismus (crossed eyes or misaligned eyes) in adults and children ages 12 years and older
• treating severe axillary hyperhidrosis (excessive underarm sweating) in adults

About the conditions Botox treats

Botox is used to treat several seemingly unrelated conditions. But what each of these conditions has in common is that they all result from a nerve problem. Specifically, these conditions occur because certain nerves don’t function properly. Instead, the nerves become overactive and send excessive signals.

For example, with migraine, nerves in your brain send signals that lead to migraine attacks. With excessive sweating, nerves in your skin send signals that over-activate your sweat glands. With atypical muscle contractions, certain nerves send signals that cause your muscles to contract in an inappropriate and uncontrollable way.

What Botox does

Botox is made from a toxin that’s produced by Clostridium botulinum bacteria. It’s a type of drug called a neurotoxin. Botox works by stopping nerves from functioning.

Typically, nerves communicate with other parts of your body, such as your muscles. Your nerves do this by releasing a neurotransmitter (chemical messenger) called acetylcholine. Botox works by stopping nerve endings from releasing acetylcholine. This leaves the nerves temporarily unable to send signals.

When it’s injected into specific muscles, Botox stops nerves from sending the signals that cause those muscles to contract or spasm. This weakens or paralyzes the muscle. Botox works to treat certain conditions when injected into specific muscles, as follows:

• Limb spasticity: Botox stops the muscle contractions in your arm, hand, or leg that are causing stiffness.
• Cervical dystonia: Botox stops the muscle contractions in your neck that are causing atypical head and neck position.
• Blepharospasm: Botox reduces blinking.
• Strabismus: Botox stops the affected muscles from turning your eye in the wrong direction.
• Urinary incontinence: Botox stops excessive muscle contractions in your bladder wall that cause urinary leakage.
• Migraine: Botox stops certain nerves from sending signals that are involved in causing migraine attacks.

When it’s injected into your skin, as it is with excessive sweating, Botox stops certain nerves from sending signals. These signals activate your sweat glands and cause you to sweat.

Botox’s effect wears off gradually as your nerves develop new endings and start to release acetylcholine again. This process typically takes about 3 months. But if recommended by your doctor, Botox injections can be repeated when the drug’s effect goes away.

How long does it take for Botox to work?

Botox starts to have its effect on nerve endings in your body within 24–72 hours after it’s injected. But it typically takes up to 2 weeks before the drug has its full effect and you notice a difference in your symptoms. However, for some people, it can take longer than 2 weeks for this to occur.

How Botox is given

Botox is given during treatment sessions. At each session, you’ll likely receive several injections of the drug. The injections are given into different areas of the body, depending on the condition being treated.

Botox injection sites

For most of its uses, Botox is given by intramuscular injection. It’s injected into muscles in different areas of your body, depending on the condition being treated.

For OAB and urinary incontinence (involuntary leaking of urine) due to nerve disorders, Botox is injected into the detrusor muscle of the bladder. This injection is done using a thin tube called a cystoscope that’s inserted into your bladder.

And for excessive underarm sweating, Botox is injected into the skin of your armpit.

Injection sites for chronic migraine

For chronic migraine, you’ll receive two or more Botox injections in each of the following areas of your body:

• lower part of your forehead, just above your nose and the inside edge of each eyebrow
• middle of your forehead, above each eye
• behind each temple, above the ear
• back of your head, behind each ear
• back of your neck, at the base of your skull on both your right and left side
• between your shoulder and your neck on both your right and left side

Note: To learn about chronic migraine, see the “Botox for chronic migraine” section above.

Injection sites for other conditions

Below, we describe Botox injection sites for the following conditions:

• Overactive bladder (OAB): For OAB, Botox injections are given into the wall of your bladder. The injections are given through a thin tube called a cystoscope that’s inserted into your bladder through your urethra. The procedure may be done under a local anesthetic* or general anesthetic.†
• Urinary incontinence caused by a nerve disorder: As with OAB, Botox injections are given into the wall of your bladder for urinary incontinence. These injections are also given through a cystoscope with either local or general anesthetic.
• Upper limb spasticity: For upper limb spasticity, Botox injections are given just above the elbow, in the forearm, and near the thumb.
• Lower limb spasticity: For lower limb spasticity, Botox injections are given in the calf.
• Cervical dystonia: For cervical dystonia, Botox injections are given in the neck.
• Severe axillary hyperhidrosis: For hyperhidrosis, Botox injections are given in the armpits.
• Blepharospasm: For blepharospasm (uncontrollable blinking), Botox injections are given in the upper and lower eyelids.
• Strabismus: For strabismus, Botox injections are given in the muscles that move your eye. This procedure may be done with a local anesthetic.*

* With a local anesthetic, a numbing medication is used in the area of the Botox injection so that you don’t feel pain.
† With general anesthetic, a medication is given that temporarily makes you unconscious so that you don’t feel pain.

For strabismus, limb spasticity, and cervical dystonia, your doctor will measure the electrical activity in your muscles before giving Botox injections. Doing this allows your doctor to determine exactly which muscles are affected. They can then place Botox injections precisely where they’re needed.

Note: To learn about the conditions listed above, see the “Other uses for Botox” section above.

Botox and pregnancy

It’s not known whether it’s safe to receive Botox injections while you’re pregnant. This drug’s use during human pregnancy hasn’t been studied. In animal studies, the drug did cause fetal harm when given to pregnant animals. However, animal studies don’t always predict what will happen in humans.

If you’re pregnant or planning to become pregnant, talk with your doctor about whether Botox is right for you. And if you become pregnant after receiving a Botox injection, contact your doctor right away.

Botox and birth control

It’s not known whether it’s safe to have Botox injections during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re receiving Botox.

For more information about taking Botox during pregnancy, see the “Botox and pregnancy” section above.

Botox and breastfeeding

It’s not known whether Botox passes into breast milk or whether it affects how your body makes breast milk. And it’s also not known whether the drug can affect a child who’s breastfed.

If you’re breastfeeding or plan to breastfeed, talk with your doctor about whether Botox is right for you.

Botox dosage

The Botox dosage your doctor prescribes will depend on several factors. These include:

• the type and severity of the condition you’re receiving Botox to treat
• your age
• other medical conditions you may have

The following information describes dosages that are commonly used or recommended. However, your doctor will determine the best dosage to fit your needs.

Drug forms and strengths

Botox comes as a powder inside single-use vials. It’s mixed with liquid to form a solution that’s given as an injection. You’ll receive Botox injections from a healthcare professional.

For most of its uses, Botox is given by intramuscular injection. It’s injected into muscles in different areas of your body, depending on the condition being treated.

For OAB and urinary incontinence (involuntary leaking of urine) caused by a nerve disorder, Botox is injected into the detrusor muscle of the bladder. This injection is done using a thin tube called a cystoscope that’s inserted into your bladder.

And for excessive sweating, Botox is injected into the skin of your armpit.

Botox is available in two strengths: 100 units and 200 units.

Dosage for chronic migraine

The recommended dosage of Botox for chronic migraine is 155 units. This total dose is given as 31 injections of 5 units each. The injections are given into recommended injection sites, which are described in the “How Botox is given” section above.

Botox treatment for chronic migraine is typically repeated once every 12 weeks.

Note: To learn more about chronic migraine, see the “Botox for chronic migraine” section above.

Dosage for overactive bladder

The recommended dosage of Botox for overactive bladder (OAB) is 100 units. This total dose is given as 20 injections of 5 units each. The injections are given 1 centimeter (cm) apart into your bladder wall. This injection procedure is described further in the “How Botox is given” section above.

Botox treatment for OAB may be repeated when the drug’s effect wears off. However, each treatment session must be at least 12 weeks apart.

Note: To learn more about OAB, see the “Other uses for Botox” section above.

Dosage for urinary incontinence caused by a nerve disorder

The recommended dosage of Botox for urinary incontinence (involuntary leaking of urine) caused by a nerve disorder is 200 units. This total dose is given as 30 injections of 6.7 units each. The injections are given 1 cm apart into your bladder wall. This injection procedure is described further in the “How Botox is given” section above.

Botox treatment for urinary incontinence may be repeated when the drug’s effect wears off. But each treatment session must be at least 12 weeks apart.

Note: To learn more about urinary incontinence caused by a nerve disorder, see the “Other uses for Botox” section above.

Dosage for upper and lower limb spasticity

The typical dosage of Botox for upper limb spasticity in adults is 75–400 units. For lower limb spasticity in adults, the typical dosage of Botox is 300–400 units. Dosages for limb spasticity in children are described below in the “Pediatric dosage” section.

The exact Botox dosage for this use depends on the size, location, and number of muscles affected. It also depends on the severity of your spasticity. The total recommended dosage for spasticity is divided into multiple injections into affected muscles.

Botox treatment for spasticity may be repeated when the drug’s effect wears off. But each treatment session must be at least 12 weeks apart.

Your doctor will start your treatment by giving you the lowest recommended Botox dosage for spasticity. Your dose may change each time you have a session for Botox injections. Your dosage will vary depending on how your body responded to previous injections.

Note: To learn more about upper and lower limb spasticity, see the “Other uses for Botox” section above.

Dosage for cervical dystonia

The dosage of Botox for cervical dystonia depends on the severity of the condition, level of pain it’s causing, and muscles affected. The total recommended dosage of Botox for cervical dystonia is divided into multiple injections into the affected muscles.

In clinical trials, the average dose of Botox given for cervical dystonia was 236 units. Typically, treatment is started with a lower dose that may be increased depending on how your body responds to the drug.

Botox treatment for cervical dystonia may be repeated when the drug’s effect wears off. This time frame is typically 12 weeks after a treatment session.

Note: To learn more about cervical dystonia, see the “Other uses for Botox” section above.

Dosage for severe axillary hyperhidrosis

The recommended dosage of Botox for severe axillary hyperhidrosis is 50 units per armpit. This total recommended dose for each armpit is split into 10–15 injections. The injections are given 1–2 cm apart over each armpit.

Botox treatment for severe axillary hyperhidrosis may be repeated when the drug’s effect wears off. For this purpose, repeat Botox treatment is typically done at least 8 weeks after the first injection.

Note: To learn more about severe axillary hyperhidrosis, see the “Other uses for Botox” section above.

Dosage for blepharospasm

The recommended starting dosage of Botox for blepharospasm (uncontrollable blinking) is 1.25–2.5 units. This total recommended dose is given as the following three injections into each affected eye:

• two injections into the upper eyelid
• one injection into the lower eyelid

Botox treatment for blepharospasm may be repeated when the drug’s effect wears off. This time frame is typically 12 weeks after a treatment session.

Your doctor may recommend a higher dose of Botox each time you receive a set of injections. But this depends on how your body responds to previous injections. However, doses that are higher than 5 units per injection site are unlikely to be more effective than lower doses.

Note: To learn more about blepharospasm, see the “Other uses for Botox” section above.

Dosage for strabismus

The recommended starting dosage of Botox for strabismus depends on which muscle is affected. However, the typical starting dosage ranges between 1.25 units to 5 units. This total dose is given as one injection into each affected muscle.

Botox treatment for this condition may be repeated when the drug’s effect wears off. The time frame for this is typically 12 weeks after a treatment session. But for strabismus, a single Botox injection may correct the condition.

If you have repeat treatment, your doctor may recommend a higher dosage of Botox each time you receive Botox injections. But this depends on how your body responds to previous injections. The maximum recommended dosage of Botox for this use is 25 units into any one muscle.

Note: To learn more about strabismus, see the “Other uses for Botox” section above.

Pediatric dosage

Botox is approved for certain uses in children. Below, we list these uses and describe the typical recommended dosage for each of them.

Note: To learn more about the conditions listed below, see the “Other uses for Botox” section above.

Dosage for upper and lower limb spasticity

Botox is approved to treat upper and lower limb spasticity in children ages 2 years and older. The typical dosage for this use is based on the child’s body weight.

Botox dosage for spasticity depends on the size, location, and number of muscles affected. It also depends on the severity of the child’s spasticity. The total dosage calculated is divided into multiple injections, which are given into the affected muscles.

Botox treatment for spasticity may be repeated when the drug’s effect wears off. However, each treatment session must be at least 12 weeks apart.

Your child’s doctor will start your child’s treatment with the lowest recommended Botox dosage for spasticity. The dosage recommended by the doctor may change each time Botox is given. Dosages will depend on how your child responds to previous injections.

Dosage for upper limb spasticity in children

The recommended dosage for upper limb spasticity is 3–6 units per kilogram (kg) of body weight. The total dose given in one treatment session shouldn’t be higher than either 6 units of Botox per kg of body weight or 200 units, whichever amount is lower.

Dosage for lower limb spasticity in children

The recommended dosage for lower limb spasticity is 4–8 units per kg of body weight. The total dose given in one treatment session shouldn’t be higher than 8 units per kg of body weight or 300 units, whichever amount is lower.

Dosage for limb spasticity affecting more than one limb in children

In some cases, both the right and left leg, or both the arms and legs, are treated with Botox. In these cases, the total Botox dosage in a 3-month period shouldn’t be greater than either 10 units per kg of body weight or 340 units, whichever amount is lower.

Dosage for blepharospasm

The recommended dosage of Botox for blepharospasm (uncontrollable blinking) in children is the same as that for adults. See the section above for details.

Dosage for strabismus

The recommended dosage of Botox for strabismus in children is the same as that for adults. See the section above for details.

What if I miss a dose?

If you miss an appointment for your Botox injections, call your doctor’s office to reschedule.

To help make sure that you don’t miss an appointment for your injections, try setting a reminder on your phone. A note on your calendar may be helpful, too.

Will I need to use this drug long term?

Botox is meant to be used as a long-term treatment for most of its approved conditions. For these conditions, the drug may be given repeatedly as your doctor recommends. But for strabismus, a single Botox injection may correct the condition.

If you and your doctor determine that Botox is safe and effective for you, you’ll likely use the drug long term for most conditions.

Common questions about Botox

Here are answers to some frequently asked questions about Botox.

Does Botox for migraine help to reduce wrinkles?

It may, depending on where the wrinkles are. But Botox for migraine isn’t approved for this use.

Botox, which is approved to manage migraine and other health conditions, is a different medication than Botox Cosmetic. Both medications contain the same drug. However, Botox Cosmetic is approved to reduce wrinkles.

For migraine treatment, Botox is injected into some of the same places on your forehead where Botox Cosmetic is injected. Like Botox Cosmetic injections, Botox injections can help reduce frown lines between your eyebrows. The injections can also reduce horizontal creases in your forehead.

However, Botox is unlikely to help reduce wrinkles around your eyes (called crow’s feet lines) because it’s not injected into the areas that would help reduce these wrinkles.

If you have questions about Botox and Botox Cosmetic, see “Botox vs. Botox Cosmetic” near the beginning of this article or talk with your doctor. You can also see this article for a comparison of the cosmetic and medical uses of Botox.

What will happen if I stop Botox?

If you stop treatment with Botox, the drug’s effects tend to wear off after about 12 weeks from your last injection. In some cases, this can lead to your condition coming back. With chronic migraine, the condition may even become worse than it was before treatment.

If you have questions about stopping Botox treatment, talk with your doctor. They can discuss with you how stopping treatment will affect your condition.

Is Botox a steroid?

No, Botox isn’t a steroid. Steroids (also called corticosteroids) are drugs that reduce inflammation in your body.

Instead, Botox is a neurotoxin. It works by stopping nerves from sending messages. Botox is made from a toxin that’s produced by Clostridium botulinum bacteria.

Is Botox safe for older adults to use?

Yes, in general, Botox is safe for use in older adults (people ages 65 years and older). In clinical trials, there weren’t any differences in the overall safety of the drug between older adults and younger adults.

However, when Botox was used for overactive bladder (OAB),* certain side effects were more common in older adults than in younger adults. These side effects were urinary tract infections (UTIs) and difficulty emptying the bladder.

If you have questions about the safety of Botox given your age, talk with your doctor.

* To learn about OAB, see the “Other uses for Botox” section above.

Is Botox used to treat vestibular migraine?

Botox hasn’t been specifically studied for treating vestibular migraine. So it’s not known whether Botox is an effective treatment for this condition.

With vestibular migraine, you have repeated attacks of dizziness or vertigo (spinning sensations). Your hearing and vision may also be affected. These attacks may be associated with other symptoms of migraine, such as nausea and headache. But they may also occur on their own.

Your doctor may prescribe Botox for vestibular migraine. But keep in mind that this is an off-label use. (With off-label use, a drug that’s approved for certain conditions is prescribed for a different condition.)

If you’re interested in receiving Botox for vestibular migraine, talk with your doctor. They can recommend appropriate treatment options for your condition.

Alternatives to Botox

Other drugs are available that can treat your condition. Some may be a better fit for you than others. If you’re interested in finding an alternative to Botox, talk with your doctor. They can tell you about other medications that may work well for you.

For information about the conditions Botox is used for, see the “Botox for chronic migraine” and “Other uses for Botox” sections above.

Note: Some of the drugs listed here are prescribed off-label to treat these specific conditions. Off-label use is when a drug that’s approved to treat one condition is prescribed to treat a different condition.

Alternatives for chronic migraine

Examples of other drugs that may be prescribed to prevent headaches from chronic migraine include:

• certain beta-blockers, such as:
  • propranolol (Inderal LA)
  • metoprolol (Lopressor, Toprol XL)
• certain calcium channel blockers, such as:
  • verapamil
  • nifedipine
• certain antidepressants, such as:
  • amitriptyline
  • venlafaxine (Effexor XR)
• certain seizure medications, such as:
  • topiramate (Topamax, Trokendi XR)
  • divalproex sodium (Depakote)
  • sodium valproate
• calcitonin gene-related peptide (CGRP) antagonists, such as:
  • erenumab-aooe (Aimovig)
  • fremanezumab-vrfm (Ajovy)
  • galcanezumab-gnlm (Emgality)

Alternatives for urinary or bladder disorders

Examples of other drugs that may be prescribed to treat urinary or bladder disorders include:

• anticholinergic drugs, such as:
  • oxybutynin
  • solifenacin (Vesicare)
  • tolterodine (Detrol)
  • fesoterodine (Toviaz)
  • trospium
  • darifenacin
• imipramine (Tofranil)
• mirabegron (Myrbetriq)

Alternatives for upper and lower limb spasticity

Examples of other drugs that may be prescribed to treat upper and lower limb spasticity include:

• baclofen (Gablofen, Lioresal, Ozobax DS)
• gabapentin (Neurontin)
• diazepam (Valium)
• dantrolene sodium (Dantrium)
• abobotulinumtoxinA (Dysport)
• incobotulinumtoxinA (Xeomin)

Alternatives for cervical dystonia

Examples of other drugs that may be prescribed to treat cervical dystonia include:

• diazepam (Valium)
• topiramate (Topamax)
• trihexyphenidyl
• benztropine
• levodopa/carbidopa (Sinemet)
• abobotulinumtoxinA (Dysport)
• incobotulinumtoxinA (Xeomin)
• rimabotulinumtoxinB (Myobloc)

Alternatives for severe axillary hyperhidrosis

Examples of other drugs that may be prescribed to treat severe axillary hyperhidrosis include:

• oxybutynin
• benztropine
• glycopyrronium (Qbrexza)

Alternatives for eye muscle problems, such as blepharospasm or strabismus

Examples of other drugs that may be prescribed to treat eye muscle problems, such as blepharospasm (uncontrollable blinking) or strabismus (crossed eyes or misaligned eyes), include:

• incobotulinumtoxinA (Xeomin)

Botox vs. Aimovig

You may wonder how Botox compares with other medications that are prescribed for similar uses. Here we look at how Botox and Aimovig are alike and different.

Ingredients

Botox contains the drug onabotulinumtoxinA, while Aimovig contains the drug erenumab-aooe.* These drugs belong to different classes of medications. (A medication class describes a group of drugs that work in the same way.)

* The reason “-aooe” appears at the end of the drug’s name is to show that the drug is distinct from similar medications that may be created in the future.

Uses

Botox is FDA-approved for the following uses:

• preventing headaches in adults with chronic migraine
• treating overactive bladder (OAB) in adults with urinary incontinence (involuntary leaking of urine), urgency, and frequency
• treating urinary incontinence caused by a nerve disorder, such as multiple sclerosis (MS) or spinal cord injury, in adults and children ages 5 years and older
• treating upper or lower limb spasticity (involuntary muscle contractions) in adults and children ages 2 years and older
• treating cervical dystonia (involuntary muscle spasms in the neck) in adults
• treating blepharospasm (uncontrollable blinking) related to dystonia (involuntary muscle spasms) in adults and children ages 12 years and older
• treating strabismus (crossed eyes or misaligned eyes) in adults and children ages 12 years and older
• treating severe axillary hyperhidrosis (excessive underarm sweating) in adults

Botox is approved to treat each of these conditions in certain situations. To learn more about receiving Botox for these conditions, see the “Botox for chronic migraine” and “Other uses for Botox” sections above.

Aimovig is approved only for preventing migraine in adults.

Drug forms and administration

Botox comes as a powder inside single-use vials. It’s mixed into a solution and given as an injection by healthcare professionals.

For most of its uses, Botox is given by intramuscular injection. It’s injected into muscles in different areas of your body, depending on the condition being treated.

For OAB and urinary incontinence caused by a nerve disorder, Botox is injected into the detrusor muscle of the bladder. This injection is done using a thin tube called a cystoscope that’s inserted into your bladder.

And for excessive sweating, Botox is injected into the skin of your armpit.

Botox injections are typically given once every 12 weeks.

Aimovig is a solution that comes in two forms: a prefilled autoinjector pen and a prefilled syringe. It’s given by subcutaneous injection once per month. You can give Aimovig injections to yourself at home after a healthcare professional shows you how.

Side effects and risks

Botox and Aimovig can cause some similar side effects, but some different ones as well. Below are examples of these side effects.

Mild side effects

These lists contain up to 10 of the most common mild side effects that can occur with Botox, with Aimovig, or with both drugs (when taken individually).

• Can occur with Botox:
  • tenderness, swelling, bruising, bleeding, or infection at Botox injection sites
  • unwanted muscle weakness near Botox injection sites
  • nausea
  • fever
  • achy muscles
  • upper respiratory tract infections, such as the common cold
  • headache
  • neck pain
  • drooping eyelids
• Can occur with Aimovig:
  • muscle cramps
• Can occur with both Botox and Aimovig:
  • muscle spasms
  • constipation
  • discoloration, itching, and pain at injection sites

Serious side effects

These lists contain examples of serious side effects that can occur with Botox, with Aimovig, or with both drugs (when taken individually).

• Can occur with Botox:
  • spread of toxin effects, which may lead to difficulty breathing or swallowing that may be life threatening*
  • corneal ulceration (open sore on the clear covering over the front of the eye) due to reduced blinking in people receiving Botox for blepharospasm
  • urinary retention (inability to empty the bladder) in people receiving Botox for urinary incontinence
  • retrobulbar hemorrhage (bleeding behind the eye) in people receiving Botox to treat strabismus
  • autonomic dysreflexia (a serious complication of the central nervous system) in people receiving Botox to treat urinary incontinence due to a neurological condition
• Can occur with Aimovig:
  • severe constipation that may need to be treated in hospital or require surgery
  • high blood pressure that leads to hospitalization
• Can occur with both Botox and Aimovig:
  • severe allergic reaction

* Botox has a boxed warning about this risk. This is the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Effectiveness

Botox and Aimovig have different FDA-approved uses, but they’re each prescribed to help prevent headaches caused by chronic migraine. (Aimovig is also approved to help prevent headaches from episodic migraine, while Botox is not.)

These drugs haven’t been directly compared in clinical trials. However, separate clinical trials have found both Botox and Aimovig to be effective in preventing chronic migraine.

Costs

The actual price you’ll pay for either drug depends on your insurance plan and your location. It may also depend on the cost of the visit to your healthcare professional to receive doses.

Botox and Aimovig are both brand-name drugs. There are currently no biosimilar forms of either drug.

Biologic medications are made from living cells, so it’s not possible to copy these drugs exactly. Generics, on the other hand, are drugs made from chemicals. A generic is an exact copy of the active drug in a brand-name medication.

Biosimilar medications are considered just as safe and effective as their parent drug. And as with generics, biosimilars tend to cost less than brand-name medications.

Botox vs. Topamax

You may wonder how Botox compares with other medications that are prescribed for similar uses. Here we look at how Botox and Topamax are alike and different.

Ingredients

Botox contains the drug onabotulinumtoxinA, while Topamax contains the drug topiramate. These drugs belong to different classes of medications. (A medication class describes a group of drugs that work in the same way.)

Uses

Botox is FDA-approved for the following uses:

• preventing headaches in adults with chronic migraine
• treating overactive bladder (OAB) in adults with urinary incontinence (involuntary leaking of urine), urgency, and frequency
• treating urinary incontinence caused by a nerve disorder, such as multiple sclerosis (MS) or spinal cord injury, in adults and children ages 5 years and older
• treating upper or lower limb spasticity (involuntary muscle contractions) in adults and children ages 2 years and older
• treating cervical dystonia (involuntary muscle spasms in the neck) in adults
• treating blepharospasm (uncontrollable blinking) related to dystonia (involuntary muscle spasms) in adults and children ages 12 years and older
• treating strabismus (crossed eyes or misaligned eyes) in adults and children ages 12 years and older
• treating severe axillary hyperhidrosis (excessive underarm sweating) in adults

Botox is approved to treat each of these conditions in certain situations. To learn more about receiving Botox for these conditions, see the “Botox for chronic migraine” and “Other uses for Botox” sections above.

Topamax is approved for the following uses:

• preventing migraine in adults and children ages 12 years and older
• treating epilepsy (specifically, focal onset seizures or primary generalized tonic-clonic seizures) in adults and children ages 2 years and older*
• treating epilepsy (specifically, focal onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome) in adults and children ages 2 years and older†

* For this purpose, Topamax is taken alone.
† For this purpose, Topamax is taken in combination with other treatments.

Drug forms and administration

Botox comes as a powder inside single-use vials. It’s mixed into a solution and given as an injection by healthcare professionals.

For most of its uses, Botox is given by intramuscular injection. It’s injected into muscles in different areas of your body, depending on the condition being treated.

For OAB and urinary incontinence caused by a nerve disorder, Botox is injected into the detrusor muscle of the bladder. This injection is done using a thin tube called a cystoscope that’s inserted into your bladder.

And for excessive sweating, Botox is injected into the skin of your armpit.

Botox injections are typically given once every 12 weeks.

Topamax comes as tablets and capsules that are taken by mouth. It’s taken twice each day.

Side effects and risks

Botox and Topamax can cause some similar and some different side effects. Below are examples of these side effects.

Mild side effects

These lists contain up to 10 of the most common mild side effects that can occur with Botox, with Topamax, or with both drugs (when taken individually).

• Can occur with Botox:
  • pain, tenderness, discoloration, swelling, bruising, bleeding, or infection at Botox injection sites
  • unwanted muscle weakness near Botox injection sites
  • achy muscles
  • neck pain
  • drooping eyelids
• Can occur with Topamax:
  • pins and needles sensations in your body
  • loss of appetite
  • weight loss
  • diarrhea
  • problems with concentration, memory, or speech
  • changes in taste
  • sleepiness
• Can occur with both Botox and Topamax:
  • nausea
  • fever
  • headache
  • dizziness
  • upper respiratory tract infections, such as the common cold

Serious side effects

These lists contain examples of serious side effects that can occur with Botox, with Topamax, or with both drugs (when taken individually).

• Can occur with Botox:
  • spread of toxin effects, which may lead to difficulty breathing or swallowing that may be life threatening*
  • corneal ulceration (open sore on the clear covering over the front of the eye) due to reduced blinking in people receiving Botox for blepharospasm
  • urinary retention (inability to empty the bladder) in people receiving Botox for urinary incontinence
  • retrobulbar hemorrhage (bleeding behind the eye) in people receiving Botox to treat strabismus
  • autonomic dysreflexia (a serious complication of the central nervous system) in people receiving Botox to treat urinary incontinence due to a neurological condition
• Can occur with Topamax:
  • eye problems, such as vision changes or raised pressure in the eye
  • reduced sweating and increased body temperature
  • metabolic acidosis (increased level of acid in the blood)
  • high level of ammonia in the blood
  • suicidal thoughts or actions
  • serious skin reactions
  • kidney stones
  • fetal harm if taken during pregnancy
• Can occur with both Botox and Topamax:
  • severe allergic reaction

* Botox has a boxed warning about this risk. This is the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Effectiveness

Botox and Topamax have different FDA-approved uses, but they’re each used to help prevent headaches caused by chronic migraine. (Topiramate is also approved to help prevent headaches from episodic migraine, while Botox is not.)

The use of Botox and Topamax for migraine prevention has been directly compared in a 2019 clinical trial. In this study, Botox was more effective in preventing chronic migraine headaches.

If you’re interested in taking one of these drugs to prevent migraine headaches, talk with your doctor about which drug is right for you.

Costs

The actual price you’ll pay for either drug depends on your insurance plan and your location. If you’re prescribed Botox, it also depends on the cost of the visit to your healthcare professional to receive doses of this drug.

Botox and Topamax are both brand-name drugs. A generic form of Topamax is available. However, there’s currently no biosimilar form of Botox.

Biologic medications are made from living cells, so it’s not possible to copy these drugs exactly. Generics, on the other hand, are drugs made from chemicals. A generic is an exact copy of the active drug in a brand-name medication.

Biosimilar medications are considered just as safe and effective as their parent drug. And as with generics, biosimilars tend to cost less than brand-name medications.

Botox and alcohol

Botox isn’t known to interact with alcohol. Alcohol doesn’t affect how this drug works. However, drinking alcohol after having Botox injections could increase your risk of certain side effects. Examples of these side effects include:

• headache
• dizziness
• tiredness
• blurred vision

If you drink alcohol, talk with your doctor about how much is safe for you to drink while you’re receiving Botox.

Botox interactions

Botox can interact with several other medications. Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.

Botox and other medications

Below are lists of medications that can interact with Botox. These lists don’t contain all the drugs that may interact with Botox.

Before taking Botox, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Botox and blood thinners

Botox injections can cause bruising or bleeding. But the injections are more likely to do this if you also take blood thinning drugs.

Examples of blood thinning drugs include:

• anticoagulants, such as:
  • warfarin
  • rivaroxaban (Xarelto)
  • apixaban (Eliquis)
• antiplatelets, such as:
  • aspirin
  • dipyridamole (Persantine)

If you take a blood thinning drug, talk with your doctor about your risk of bruising or bleeding with Botox. Your doctor may recommend that you stop the blood thinner temporarily before you receive Botox injections.

Botox and anticholinergics

Anticholinergics are used to treat a variety of conditions, including urinary incontinence and movement disorders such as Parkinson’s disease.

Taking an anticholinergic drug while receiving Botox injections can increase your risk of certain side effects. These side effects include blurred vision, dry mouth, dry eyes, and difficulty urinating.

Examples of anticholinergic drugs that can increase your risk of side effects with Botox include:

• oxybutynin
• solifenacin (Vesicare)
• tolterodine (Detrol)
• fesoterodine (Toviaz)
• trospium
• darifencin
• trihexyphenidyl
• benztropine

If you take an anticholinergic drug, talk with your doctor before starting Botox. They can recommend whether you should continue taking the drug while you’re receiving Botox injections.

Botox and muscle relaxants

Botox can cause unwanted muscle weakness around the area where the drug is injected. And taking a muscle relaxant medication before or after having a Botox injection can increase your risk of this side effect.

Examples of muscle relaxants include:

• baclofen (Gablofen, Lioresal, Ozobax DS)
• diazepam (Valium)
• dantrolene sodium (Dantrium)

If you take a muscle relaxant, talk with your doctor. They can recommend whether you should continue taking it while you’re having Botox injections.

Keep in mind that certain muscle relaxants are sometimes given with anesthesia during surgical procedures. If you have any surgeries, be sure to tell your doctor if you’re receiving Botox.

Botox and certain antibiotics

Certain antibiotics can increase the risk of side effects such as unwanted muscle weakness from Botox.

Examples of these antibiotics include:

• neomycin
• amikacin
• gentamicin
• tobramycin

If you’ve recently had treatment with one of these antibiotics, be sure to tell your doctor before receiving Botox injections. Your doctor will recommend whether it’s safe for you to have Botox.

If you need treatment with one of these antibiotics, let your doctor know if you’re receiving Botox. Your doctor will advise whether the antibiotic is safe for you to take or if you should take a different antibiotic instead.

Botox and other botulinum toxin products

Botox contains the drug onabotulinumtoxinA. It’s made from a toxin that’s produced by Clostridium botulinum bacteria. If Botox is given at the same time as, or within a few months of, other botulinum toxin products, it can cause severe muscle weakness.

Examples of other botulinum toxin products include:

• rimabotulinumtoxinB (Myobloc)
• abobotulinumtoxinA (Dysport)
• incobotulinumtoxinA (Xeomin)

If you’ve received any other botulinum toxin product, be sure to tell your doctor before getting a Botox injection. Botox should not be given until the effects of the other product have worn off.

Botox and herbs and supplements

There aren’t any herbs or supplements that have been specifically reported to interact with Botox. However, you should still check with your doctor or pharmacist before using any of these products while taking Botox.

Botox and foods

There aren’t any foods that have been specifically reported to interact with Botox. If you have any questions about eating certain foods with Botox, talk with your doctor.