ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.
Overview
Effects last about 3 months.
What it's used for
- Chronic migraine prevention
- Overactive bladder
- Excessive underarm sweating
- Spasticity and neck dystonia
- Eye muscle spasms
How to take it
- Given by a trained clinician as injections every 12 weeks or so.
Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.
Side effects
Common side effects
- Neck pain or weakness
- Pain at injection sites
- Droopy eyelid (face injections)
Call 911Trouble swallowing, speaking, or breathing in the days or weeks after injection
Warnings
- Boxed warning: the toxin can spread beyond the injection site.
Other medicines, foods, and alcohol
- Some antibiotics (aminoglycosides) and muscle relaxants add to its effect.
Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.
Pregnancy and breastfeeding
Not usually used in pregnancy.
Missed doses, overdose, and storage
If you miss a dose
Not applicable: it's given in a clinic on a schedule.
If someone takes too much
Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.
Storing it
Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.
Conditions it's used for
Sources
- DailyMed: FDA drug label for OnabotulinumtoxinA (U.S. National Library of Medicine)
- MedlinePlus: Drugs, herbs, and supplements
- FDA: Drugs@FDA
Last updated 2026-11-13.