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OnabotulinumtoxinA

Generic name: onabotulinumtoxinA (Botox) [ ON-a-BOT-ue-LYE-num-TOX-in-A ]
Brand names: Botox, Botox Cosmetic
Dosage form: injectable powder for injection (100 units; 200 units; 50 units)
Drug class: Skeletal muscle relaxants

Medically reviewed by Drugs.com on Oct 14, 2022. Written by Cerner Multum.

What is onabotulinumtoxinA (Botox)?

Botox is used in adults to treat cervical dystonia (abnormal head position and neck pain).

Botox is also used to treat muscle spasms and stiffness (spasticity) of the arms, hands, legs, and feet in adults and children at least 2 years old. This medicine will not treat spasticity caused by cerebral palsy.

Botox is also used to treat certain eye muscle conditions caused by nerve disorders in adults and children who are at least 12 years old. This includes uncontrolled blinking or spasm of the eyelids, and a condition in which the eyes do not point in the same direction.

Botox is also used in adults to treat overactive bladder and incontinence (urine leakage) that has not been helped by other medication. Botox may be used to treat incontinence caused by nerve disorders such as spinal cord injury or multiple sclerosis.

Botox is also used to treat overactive bladder caused by a neurologic disorder (such as multiple sclerosis or spinal cord injury) in children at least 5 years old when other medicines cannot be used or have not worked.

Botox is also used in adults to prevent chronic migraine headaches that occur more than 15 days per month and last 4 hours or longer. Botox should not be used to treat a common tension headache.

Botox is also used to treat severe underarm sweating (hyperhidrosis) in adults.

Botox Cosmetic is used to temporarily lessen the appearance of facial wrinkles in adults.

Botox may also be used for purposes not listed in this medication guide.

OnabotulinumtoxinA (Botox) side effects

Get emergency medical help if you have signs of an allergic reaction: hives, itching; wheezing, difficult breathing; feeling like you might pass out; swelling of your face, lips, tongue, or throat.

The botulinum toxin contained in Botox can spread to other body areas beyond where it was injected. This has caused serious life-threatening side effects in some people receiving botulinum toxin injections, even for cosmetic purposes.

Call your doctor at once if you have any of these side effects (up to several hours or several weeks after an injection):

Common side effects of onabotulinumtoxinA may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

The botulinum toxin contained in this medicine can spread to other body areas beyond where it was injected. This can cause serious life-threatening side effects.

Call your doctor at once if you have a hoarse voice, drooping eyelids, vision problems, severe eye irritation, severe muscle weakness, loss of bladder control, or trouble breathing, talking, or swallowing.

Before taking this medicine

You should not be treated with Botox if you are allergic to botulinum toxin, or if you have:

Tell your doctor if you have ever had:

Botox is made from donated human plasma and may contain viruses or other infectious agents. Donated plasma is tested and treated to reduce the risk of contamination, but there is still a small possibility it could transmit disease. Ask your doctor about your individual risk.

Tell your doctor if you are pregnant or breastfeeding.

How is onabotulinumtoxinA (Botox) given?

Botox injections should be given only by a trained medical professional, even when used for cosmetic purposes.

This medicine is injected into a muscle by a healthcare provider. Botox injections should be spaced at least 3 months apart.

Botox injections may be given into more than one area at a time, depending on the condition being treated.

While receiving injections for eye muscle conditions, you may need to use eye drops, ointment, a special contact lens or other device to protect the surface of your eye. Follow your doctor's instructions.

If you are being treated for excessive sweating, shave your underarms about 24 hours before your injection. Do not apply antiperspirant or deodorant for 24 hours before or after you receive the injection. Avoid exercise and hot foods or beverages within 30 minutes before the injection.

It may take up to 2 weeks after injection before neck muscle spasm symptoms begin to improve. You may notice the greatest improvement after 6 weeks.

It may take only 1 to 3 days after injection before eye muscle spasm symptoms begin to improve. You may notice the greatest improvement after 2 to 6 weeks.

The effects of a Botox injection are temporary. Your symptoms may return completely within 3 months. After repeat injections, it may take less and less time before your symptoms return, especially if your body develops antibodies to the botulinum toxin.

Do not seek botulinum toxin injections from more than one medical professional at a time. If you switch healthcare providers, tell your new provider how long it has been since your last botulinum toxin injection.

Using this medication more often than prescribed will not make it more effective and may result in serious side effects.

What happens if I miss a dose?

Since botulinum toxin has a temporary effect and is given at widely spaced intervals, missing a dose is not likely to be harmful.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may not appear right away, but can include muscle weakness, trouble swallowing, and weak or shallow breathing.

What should I avoid after receiving onabotulinumtoxinA (Botox)?

Botox may impair your vision or depth perception. Avoid driving or hazardous activity until you know how this medicine will affect you.

Avoid going back to your normal physical activities too quickly after receiving an injection.

What other drugs will affect onabotulinumtoxinA (Botox)?

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may affect Botox, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Frequently asked questions

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.