Key takeaways
- Botox (onabotulinumtoxinA) is a brand-name drug that’s prescribed for various conditions, including overactive bladder and excessive sweating, in adults and some children.
- Botox comes as an injection that’s given by a healthcare professional.
- Your Botox dosage will depend on the condition being treated.
Botox is approved by the Food and Drug Administration (FDA) to:
- treat overactive bladder (OAB) with urinary incontinence, urgency, and frequency in certain adults
- treat urinary incontinence related to a nerve disorder called neurogenic detrusor overactivity (NDO) in adults and children ages 5 years and older
- prevent headache days in adults with chronic (long-term) migraine
- treat muscle spasticity in adults and children ages 2 years and older
- treat cervical dystonia (uncontrollable neck muscle spasms) in adults
- treat severe underarm sweating in adults
- treat blepharospasm (excessive eyelid twitching) and strabismus (crossed or misaligned eyes) that are related to dystonia (involuntary muscle spasms) in adults and children ages 12 years and older
Botox is a biologic and belongs to a drug class called neurotoxins. Botox is not available in a biosimilar version.
Keep reading for specific information about the dosage of Botox, including its strengths and how the medication is given.
Note: This article describes typical dosages for Botox provided by the drug’s manufacturer. However, your doctor will prescribe the Botox dosage that’s right for you.
The information below describes the FDA botox dosing guidelines and details.
Botox form
Botox comes as a powder in a single-dose vial. The powder is mixed with a liquid to form a solution for an injection. You’ll receive the injection from a healthcare professional.
Botox can be given as an injection into the muscle, second layer of the skin, or bladder. But for most uses, the drug is injected into the muscle.
Botox strengths
Botox comes in two strengths: 100 units and 200 units.
Typical dosages
The following information describes dosages that are commonly used in adults. However, your doctor will determine the best dosage to fit your needs.
Dosage for overactive bladder (OAB)
Doctors may prescribe Botox to treat OAB.
The recommended dose will likely be 100 units. This is the maximum dose of Botox that’s recommended. The dose is given as 20 injections of 5 units each. The injections are spaced 1 centimeter (cm) apart in your bladder wall.
Your doctor may repeat the dose once the drug’s effects wear off. However, the minimum time between treatment sessions is 12 weeks.
Dosage for urinary incontinence due to a nerve disorder
Botox is also approved to help treat urinary incontinence caused by a nerve disorder. In this case, the recommended dose of Botox is 200 units. This is the maximum dose of Botox that’s recommended. The dose is given as 30 injections of approximately 6.7 units each. The injections are spaced 1 cm apart in your bladder wall.
Botox treatment may be repeated once the effects of the drug wear off. However, it’s recommended to wait at least 12 weeks between treatment sessions.
Dosage for preventing chronic migraine
Doctors also prescribe Botox to prevent headache days in adults with chronic migraine. The recommended dose for this purpose is 155 units. The dose is given as 31 injections of 5 units each. The injections are given in specific muscles of your head and neck.
Botox treatment for the prevention of chronic migraine may be repeated once every 12 weeks.
Dosage for muscle spasticity
Botox is also used to treat muscle spasticity of the upper and lower limbs. Your doctor will prescribe a dose based on several factors, including the specific muscles involved, the severity of your condition, whether you have muscle weakness, and your response to previous treatments.
The typical dose of Botox for upper limb spasticity is 75 to 400 units. The dose for lower limb spasticity is 300 to 400 units. The dose is divided into multiple injections and given into the affected muscles.
If needed, Botox treatment may be repeated once every 12 weeks. However, your dose of Botox may change with each treatment session, depending on the pattern and severity of your muscle spasticity.
Dosage for cervical dystonia
Doctors may prescribe Botox for cervical dystonia. They’ll prescribe a dose of Botox based on the severity of your condition, the muscles involved, and your response to previous treatments. The dose is divided and given to the affected muscles.
In clinical trials, the average Botox dose for cervical dystonia was 236 units. Your doctor will likely prescribe a lower dose for your first Botox treatment. They may increase the dose for future treatment sessions, depending on how you respond to the drug.
Botox may be repeated for cervical dystonia once the drug’s effects wear off. It can be repeated once every 12 weeks.
Dosage for excessive underarm sweating
Botox treatment is also used to treat primary axillary hyperhidrosis (severe underarm sweating). In this case, the recommended dose is 50 units per underarm. The total dose is divided into 10 to 15 injections. The injections are given 1 to 2 cm apart in each underarm.
Botox injections may be repeated once the drug’s effect wears off.
Dosage for blepharospasm
Doctors also prescribe Botox for blepharospasm (excessive eyelid twitching). The typical starting dose is 1.25 to 2.5 units. The dose is divided into three injections into each affected eye: two injections into the upper eyelid and one injection into the lower eyelid.
If needed, Botox treatment for blepharospasm may be repeated once every 3 months. Your doctor may prescribe a higher dose each treatment session or a more frequent dosing schedule depending on how you respond to previous injections.
The maximum dose of Botox for blepharospasm is 200 units per month.
Dosage for strabismus
Botox may also be used for strabismus (crossed or misaligned eyes). Your doctor will prescribe a dose based on which muscle is affected. The typical starting dose is 1.25 to 5 units. The dose is given into each affected muscle.
Botox injections may be repeated once the effects of the previous treatment wear off.
The maximum dose of Botox for strabismus is 25 units into any one muscle.
Children’s dosage
Botox is approved to treat certain conditions in children. The dose of Botox depends on the condition being treated.
Dosage for urinary incontinence that’s related to a nerve disorder
Botox is approved to treat urinary incontinence that’s related to a nerve disorder in children ages 5 years and older.
The dosage is based on the child’s body weight in kilograms (kg). One kg equals about 2.2 pounds (lb).
If your child weighs 34 kg or greater, the recommended dose of Botox is 200 units. If your child weighs less than 34 kg, the recommended dosage is 6 units per kilogram (units/kg) of body weight.
The total dose is divided into 20 injections of 5 units each. The injections are given into the bladder wall and spaced about 1 cm apart.
Botox treatment may be repeated once the effect of the drug wears off. The minimum time between treatment sessions is 12 weeks.
Talk with your child’s doctor if you have questions about their dosage.
Dosage for muscle spasticity
Doctors prescribe Botox for upper and lower limb muscle spasticity in children ages 2 years and older.
The dosage is based on the child’s body weight in kg, how many muscles are affected, and whether the upper or lower limbs are affected.
The recommended dose for upper limb spasticity is 3 to 6 units/kg of body weight. The maximum dose of Botox per treatment session is 6 units/kg of body weight or 200 units, whichever is lower.
The typical dose for lower limb spasticity is 4 to 8 units/kg. The maximum dose of Botox per treatment session is 8 units/kg of body weight or 300 units, whichever is lower.
If both lower limbs are affected or the upper and lower limbs are affected at the same time, the maximum dose is 10 units/kg of body weight or 340 units in a 3-month period.
The total dose is divided into multiple injections and given into the affected muscles.
Dosage for blepharospasm
Botox is also approved to treat blepharospasm (excessive eyelid twitching) in children ages 12 years and older. The recommended dosage of Botox for blepharospasm in children is the same as in adults. See the “Typical dosages” section.
Dosage for strabismus
Botox is also used to treat strabismus (crossed or misaligned eyes) in children ages 12 years and older. The recommended dosage of Botox for strabismus in children is the same as in adults. See the “Typical dosages” section above.
How Botox is given
Your doctor or another healthcare professional will give you the injection of Botox. First, they’ll mix the powder form of Botox with a liquid to make a solution. Then, they’ll prepare the liquid solution for injection. You’ll likely go to your doctor’s office or clinic to receive your injection.
Depending on the condition being treated, your doctor or another healthcare professional may give Botox with a local or general anesthetic. (Anesthetics are drugs that induce anesthesia.) This helps reduce the pain you’ll feel with Botox injections.
Botox is typically given in multiple injections. The injections are given into the area of the body that’s affected by the condition being treated. For example, Botox is injected into the muscle of the bladder wall when used for overactive bladder. But for chronic migraine, Botox is injected into certain areas of the head and neck.
If you have questions about how Botox is given, talk with your doctor or pharmacist.
Long-term treatment
Botox is meant to be given as a long-term treatment for most conditions. If you and your doctor determine that Botox is safe and effective for you, you’ll likely receive it long term.
Before you start taking Botox, your doctor will discuss your treatment plan with you.
Below are some frequently asked questions about Botox.
What are the dosing guidelines for Botox when used to prevent migraine?
The recommended dose of Botox for preventing migraine is 155 units. The dose is divided into 31 injections of 5 units each. Your doctor will inject Botox into specific muscles in the head and neck.
Treatment can be repeated once every 12 weeks.
If you have more questions about Botox dosing guidelines, talk with your doctor.
What is the maximum dose of Botox?
The maximum recommended dose of Botox depends on the condition being treated.
The following Botox dosing charts hows the maximum dose that’s recommended for adults.
| Condition | Maximum dose |
| overactive bladder | 100 units per treatment session |
| urinary incontinence due to a nerve disorder called neurogenic detrusor overactivity | 200 units per treatment session |
| blepharospasm | 200 units per month |
| strabismus | 25 units into any one muscle |
| muscle spasticity | 400 units per treatment session |
| cervical dystonia | 236 units per treatment session |
| hyperhidrosis | 50 units per treatment session |
To learn more about the maximum dose of Botox for other conditions or for children, talk with your doctor.
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