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Onabotulinumtoxina (By injection)

OnabotulinumtoxinA (on-a-bot-ue-LYE-num-tox-in-ay)

Treats muscle spasms and stiffness, excessive sweating, overactive bladder, or loss of bladder control. Prevents chronic migraine headaches. Improves the appearance of forehead lines, crow's feet lines, or wrinkles on the face.

Brand Name(s):

Botox, Botox Cosmetic

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. You should not receive it if you had an allergic reaction to onabotulinumtoxinA or any other botulinum toxin product, or if you have an infection at the injection area.

How to Use This Medicine:


  • Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given by a healthcare provider as a shot under your skin or into a muscle.
  • You may be given medicine to numb the area where the shot will be injected. If you receive the medicine around your eyes, you may be given eye drops or ointment to numb the area. After your injection, you may need to wear a protective contact lens or eye patch.
  • If you are being treated for excessive sweating, shave your underarms but do not use deodorant for 24 hours before your injection. Avoid exercise, hot foods or liquids, or anything else that could make you sweat for 30 minutes before your injection.
  • The recommended treatment schedule for chronic migraine is every 12 weeks.
  • This medicine works slowly. Once your condition has improved, the medicine will last about 3 months, then the effects will slowly go away. You might need more injections to treat your condition.
    • Muscle spasms in the eyelids should improve within 3 to 10 days.
    • Eye muscle problems should improve 1 or 2 days after the injection, and the improvement should last for 2 to 6 weeks.
    • Neck pain should improve within 2 to 6 weeks.
    • Arm stiffness should improve within 4 to 6 weeks.
    • Facial lines or wrinkles should improve 1 or 2 days.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • Missed dose: Call your doctor or pharmacist for instructions.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicine can affect how onabotulinumtoxinA works. Tell your doctor if you are using any of the following:
    • Aspirin
    • Blood thinner (including ticlopidine, warfarin)
    • Medicine to treat infection (including amikacin, gentamicin, streptomycin, tobramycin)
    • Muscle relaxer
  • Tell your doctor if you have received an injection of any botulinum toxin product within the past 4 months.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have breathing or lung problems, bleeding problems, heart or blood vessel disease, or nerve or muscle problems (including Lou Gehrig disease, Lambert-Eaton syndrome, or myasthenia gravis). Tell your doctor if you have ever had face surgery or if you have a urinary tract infection or trouble urinating, diabetes, or multiple sclerosis.
  • This medicine may cause the following problems:
    • Muscle weakness, loss of bladder control, trouble swallowing, speaking, or breathing (caused by the toxin spreading to other parts of your body)
  • There are some warnings that only apply if you are receiving this medicine to treat the following:
    • Injections near the eye: This medicine may reduce blinking, which can raise the risk of eye problems such as corneal exposure and ulcers. Tell your doctor right away if you notice that you are blinking less than usual or your eyes feel dry.
    • Upper arm stiffness: This medicine may cause lung infection (including bronchitis) and breathing problems.
    • Urinary incontinence: This medicine may cause autonomic dysreflexia, which can be a life-threatening condition.
    • Overactive bladder: Check with your doctor right away if you have trouble urinating or a burning sensation while urinating.
  • This medicine may cause loss of strength, muscle weakness, blurred vision, dizziness, or drooping eyelids. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
  • This medicine is made from donated human blood. Some human blood products have transmitted viruses, although the risk is low because donors and donated blood are both tested for viruses. Talk with your doctor about this risk if you are concerned.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blurred or double vision, droopy eyelids
  • Change in how much or how often you urinate, trouble urinating, or painful urination
  • Chest pain, slow or uneven heartbeat
  • Fever, chills, cough, stuffy or runny nose, sore throat, body aches
  • Headache, increased sweating, warmth or redness in your face, neck, or arm
  • Muscle weakness
  • Trouble swallowing, talking, or breathing

If you notice these less serious side effects, talk with your doctor:

  • Pain in your neck, back, arms, or legs
  • Redness, pain, tenderness, bruising, swelling, or weakness where the shot was given

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 5/1/2020

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

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