Botox (onabotulinumtoxinA) is a prescription brand-name medication. It’s approved by the Food and Drug Administration (FDA) to prevent headaches in adults with chronic migraine.

Migraine is a condition that can cause several symptoms, including severe headaches that can be pulsing and debilitating. These tend to occur on one side of your head and can last from a few hours to a few days. Migraine is considered chronic (long term) if you have headaches that last for at least 4 hours on 15 or more days each month.

Here are the basics on Botox for the purpose mentioned above:

  • Active ingredient: onabotulinumtoxinA
  • Drug class: neurotoxin
  • Drug form: liquid solution given as an intramuscular injection
  • Available as generic: no

Read on for more information about Botox and its use in preventing headaches in adults with chronic migraine. You can also refer to this article for a comprehensive look at Botox, which is also approved to treat certain other conditions.

Using Botox to prevent headaches in adults with chronic migraine may cause mild or serious side effects. The lists below include some of the main side effects that may occur while using Botox for this purpose. To learn about other possible side effects of the drug, talk with your doctor or pharmacist. You can also visit our comprehensive article on Botox or refer to the Botox medication guide.

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

Mild side effects

Like other medications, Botox injections to prevent headaches in adults with chronic migraine can cause mild side effects. These side effects of Botox may be temporary, lasting for a few days or weeks. But if they last for a longer time, or if they bother you or become severe, it’s important to talk with your doctor or pharmacist.

Mild side effects of these Botox injections can include:

You may be wondering if Botox can cause long-term effects. Drooping eyelids caused by Botox injections usually go away on their own within a few weeks. But if you notice any side effects from Botox injections that don’t go away on their own, be sure to talk with your doctor. They can recommend treatments and adjust your medication plan as needed.

Serious side effects

Though rare, Botox injections to prevent headaches in adults with chronic migraine can cause serious side effects. Call your doctor right away if you develop serious side effects while using Botox. If the side effects seem life threatening or you think you’re having a medical emergency, call 911 or your local emergency number immediately.

Serious side effects from these Botox injections can include:

  • allergic reaction
  • spread of toxin effects, which potentially could cause life threatening swallowing or breathing difficulties*

* Botox has a boxed warning for this side effect. This is the most serious warning from the FDA. For more information, see the “Before receiving Botox” section below.

Botox is approved by the Food and Drug Administration (FDA) to prevent headaches in adults with chronic migraine.

Dosage

For the use mentioned above, the recommended dose of Botox is 155 total units divided into 31 injections. These injections will be given in seven specific muscle areas in your head and neck. Each muscle area has a number of sites where 0.1 milliliters (mL) of Botox will be injected. (In terms of units, 0.1 mL is about 5 units.) In total, the 155 units will be injected across 31 unique sites in your head and neck muscles.

You’ll likely receive the injections every 12 weeks.

Note: In addition to preventing headaches in adults with chronic migraine, Botox has other uses. The medication’s dosage may differ with the other uses. For more information, talk with your doctor.

How Botox is given

Botox’s form is a powder that comes in a single-use vial. The drug is mixed into a liquid solution. For preventing headaches in adults with chronic migraine, the medication is given as intramuscular injections. You’ll receive these from a healthcare provider.

Injection sites

Because intramuscular injections are given directly into a muscle, you may be wondering where they are injected for migraine headaches. Here are the Botox injection sites:

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

How often to use

In general, Botox injections are given every 12 weeks for preventing headaches in adults with chronic migraine. But be sure to stick to the dosing schedule your doctor recommends for you.

How much Botox costs is based on several factors. These can include your prescribed treatment regimen, the insurance plan you have, the pharmacy you use, and your location. The price is also based on the cost of the appointment to receive doses of Botox from your healthcare provider.

For estimates of how much Botox costs, see GoodRx.com.

Here are some frequently asked questions about using Botox to prevent headaches in adults with chronic migraine.

Can using Botox for migraine also help with wrinkles?

No, using Botox to prevent headaches due to chronic migraine isn’t likely to help with wrinkles.

A different medication called Botox Cosmetic is used to help with wrinkles. Botox Cosmetic contains the same active drug (onabotulinumtoxinA) as Botox, but it’s given in lower doses. And to treat wrinkles, Botox Cosmetic is given in different injection sites than those used to prevent headaches.

Botox provides relief to only the specific nerves in the muscle groups it’s injected into. So, receiving Botox injections to prevent headaches is unlikely to affect wrinkles.

If you have questions about using Botox to prevent headaches or Botox Cosmetic for wrinkles, talk with your doctor.

What can I expect when I receive Botox injections for migraine?

Botox injections to prevent headaches in adults with chronic migraine are generally safe, but they may cause some mild side effects. To learn more, see the “Botox side effects” section above. You can also refer to the “Receiving Botox injections” section above and talk with your doctor.

Botox is approved by the Food and Drug Administration (FDA) to prevent headaches in adults with chronic migraine.

The way Botox works

Botox is a type of drug called a neurotoxin, and it stops nerves from functioning.

Your nerves usually communicate with other areas of your body by using acetylcholine, which is a neurotransmitter. (Neurotransmitters are chemical messengers.)

Botox works by stopping nerves from releasing acetylcholine. This means that your nerves can’t tell muscles to spasm or contract. When used to prevent headaches, Botox blocks nerve signals that cause pain.

In some cases, people who receive Botox injections to prevent headaches experience improvements in their condition within 2 to 4 weeks. But keep in mind it can take two sets of injections and a full 6 months before you feel the maximum effects from Botox.

Migraine is a condition that can cause several symptoms, including severe headaches that can be pulsing and debilitating. These tend to occur on one side of your head and can last from a few hours to a few days. Migraine is considered chronic (long term) if you have headaches that last for at least 4 hours on 15 or more days each month.

Symptoms of migraine

Migraine symptoms tend to occur in stages.

Before a headache. It’s possible to have symptoms that begin hours or days before a headache. Some people may experience a sensory aura, which may involve vision changes, such as blind spots or light flashes. Other people have tingling or buzzing sensations or difficulty speaking.

During a headache. In this stage, you may experience a mild-to-severe pulsing, throbbing headache. This can last any time from a few hours to a few days. You may also experience nausea and vomiting. In addition, you may have increased sensitivity to light and sound.

After a headache. You may hear this referred to as the “migraine hangover.” Tiredness and irritability are common and may last for up to 2 days. During this time, you may have trouble performing regular activities due to lingering pain. Increased sensitivity to light and sound are also possible. In addition, you may have head pain that worsens with physical activity or straining.

Botox and children

Botox isn’t approved to prevent headaches in children with chronic migraine.

Two clinical studies have demonstrated the effectiveness of Botox injections for preventing headaches in adults with chronic migraine.

These studies looked at adults with chronic migraine. The participants received injections of Botox or a placebo (treatment with no active drug). They received injections in two sets, which were given 3 months apart.

Researchers compared the number of headache days that people had at the start of the study with how many they had after 6 months of treatment. The results showed that people who received Botox averaged fewer headache days than people who received a placebo.

Before you receive Botox injections for preventing headaches due to chronic migraine, there’s some important information to note. The drug may not be a safe option for you if you have certain medical conditions or other factors that affect your health. Some of these are mentioned below.

Boxed warning: Spread of toxin effects

This drug has a boxed warning. 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.

After Botox is injected, the drug may sometimes spread to other parts of the body. This can lead to a serious condition called botulism, which may cause symptoms such as:

  • muscle weakness
  • a lack of energy
  • double vision
  • drooping eyelids
  • difficulty speaking
  • hoarse voice
  • difficulty swallowing
  • difficulty breathing
  • loss of bladder control

It’s possible for botulism to occur hours, days, or weeks after receiving Botox. If you experience any of the symptoms above after having a Botox injection, you should talk with your doctor.

Rarely, the difficulty swallowing or breathing that botulism can cause can be life threatening. If you already have trouble swallowing or breathing, you may have an increased risk for these problems. Call your doctor immediately if you have trouble swallowing or breathing after receiving a Botox injection. If you think your symptoms are life threatening, call 911 or your local emergency number.

Other warnings

In addition to boxed warnings, Botox has other warnings.

If any of the following medical conditions or other health factors are relevant to you, talk with your doctor before using Botox:

Now that you’ve learned about Botox for preventing headaches due to chronic migraine, you may still have some questions. Talk with your doctor or pharmacist, who can advise you on whether Botox might be right for you.

Here are some other helpful references:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.