OnabotulinumtoxinA Injection

Brand Name(s): Botox®, Botox® Cosmetic


OnabotulinumtoxinA injection is given as a number of tiny injections intended to affect only the specific area where injected. However, it is possible that the medication may spread from the area of injection and affect muscles in other areas of the body. If the muscles that control breathing and swallowing are affected, you may develop severe problems breathing or swallowing that may last for several months and may cause death. If you have difficulty swallowing, you may need to be fed through a feeding tube to avoid getting food or drink into your lungs.

OnabotulinumtoxinA injection may spread and cause symptoms in people of any age who are being treated for any condition, although no one has yet developed these symptoms after receiving the medication at recommended doses to treat wrinkles, eye problems, headaches, or severe underarm sweating. The risk that the medication will spread beyond the area of injection is probably highest in children being treated for spasticity (muscle stiffness and tightness) and in people, who have or have ever had swallowing problems, or breathing problems, such as asthma or emphysema; or any condition that affects muscles or nerves such as amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease; condition in which the nerves that control muscle movement slowly die, causing the muscles to shrink and weaken), motor neuropathy (condition in which the muscles weaken over time), myasthenia gravis (condition that causes certain muscles to weaken, especially after activity), or Lambert-Eaton syndrome (condition that causes muscle weakness that may improve with activity). Tell your doctor if you have or have ever had any of these conditions.

Spread of onabotulinumtoxinA injection into untreated areas can cause other symptoms in addition to difficulty breathing or swallowing. Symptoms may occur within hours of an injection or as late as several weeks after treatment. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment: loss of strength or muscle weakness all over the body; double or blurred vision; drooping eyelids or brow; difficulty swallowing or breathing; hoarseness or change or loss of voice; difficulty speaking or saying words clearly; or inability to control urination.

Your doctor will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with onabotulinumtoxinA injection and each time you receive treatment. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website ( or the manufacturer's website to obtain the Medication Guide.

WHY is this medicine prescribed?

OnabotulinumtoxinA injection (Botox, Botox Cosmetic) is used to treat a number of conditions.

OnabotulinumtoxinA injection (Botox) is used to:

  • relieve the symptoms of cervical dystonia (spasmodic torticollis; uncontrollable tightening of the neck muscles that may cause neck pain and abnormal head positions) in people 16 years of age and older;
  • relieve the symptoms of strabismus (an eye muscle problem that causes the eye to turn inward or outward) and blepharospasm (uncontrollable tightening of the eyelid muscles that may cause blinking, squinting, and abnormal eyelid movements) in adults and adolescents 12 years of age and older;
  • prevent headaches in people older than 18 years of age with chronic migraine (severe, throbbing headaches that are sometimes accompanied by nausea and sensitivity to sound or light) who have 15 or more days each month with headaches lasting 4 hours a day or longer;
  • treat overactive bladder (a condition in which the bladder muscles contract uncontrollably and cause frequent urination, urgent need to urinate, and inability to control urination) in people 18 years of age and older when other medications do not work well enough or cannot be taken;
  • treat neurogenic detrusor overactivity (NDO; a bladder control condition caused by brain, spinal cord or nerve problem) in children 5 years of age and older when other medications did not help or could not be tolerated;
  • treat incontinence (leakage of urine) in people 18 years of age and older with overactive bladder (condition in which the bladder muscles have uncontrollable spasms) caused by nerve problems such as spinal cord injury or multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control), who cannot be treated with oral medication;
  • treat spasticity (muscle stiffness and tightness) of muscles in the arms and legs in adults and children 2 years of age and older;
  • treat severe underarm sweating in people 18 years of age and older who cannot be treated with products applied on the skin;


OnabotulinumtoxinA injection (Botox Cosmetic) is used to

  • temporarily smooth frown lines (wrinkles between the eyebrows) in adults 18 years of age and older,
  • temporarily smooth crow's feet lines (wrinkles near the outer corner of the eye) in adults 18 years of age and older,
  • and to temporarily smooth forehead lines in adults 18 years of age and older.

OnabotulinumtoxinA injection is in a class of medications called neurotoxins. When onabotulinumtoxinA is injected into a muscle, it blocks the nerve signals that cause uncontrollable tightening and movements of the muscle. When onabotulinumtoxinA is injected into a sweat gland, it decreases the activity of the gland to reduce sweating. When onabotulinumtoxinA is injected into the bladder, it decreases bladder contractions and blocks signals that tell the nervous system that the bladder is full.

HOW should this medicine be used?

OnabotulinumtoxinA injection comes as a powder to be mixed with a liquid and injected into a muscle, into the skin, or into the wall of the bladder by a doctor. Your doctor will choose the best place to inject the medication in order to treat your condition. If you are receiving onabotulinumtoxinA to treat frown lines, forehead lines, crow's feet lines, cervical dystonia, blepharospasm, strabismus, spasticity, urinary incontinence, overactive bladder, or chronic migraine, you may receive additional injections every 3 to 4 months, depending on your condition and on how long the effects of the treatment last. If you are receiving onabotulinumtoxinA injection to treat severe underarm sweating or neurogenic detrusor overactivity, you may need to receive additional injections once every 6 to 7 months or as recommended by your doctor when your symptoms return.

If you are receiving onabotulinumtoxinA injection to treat severe underarm sweating, your doctor will probably perform a test to find the areas that need to be treated. Your doctor will tell you how to prepare for this test. You will probably be told to shave your underarms and not to use nonprescription deodorants or antiperspirants for 24 hours before the test.

If you are receiving onabotulinumtoxinA injection to treat urinary incontinence, your doctor may prescribe antibiotics for you to take for 1-3 days before your treatment, on the day of your treatment and for 1 to 3 days after your treatment.

Your doctor may change your dose of onabotulinumtoxinA injection to find the dose that will work best for you.

Your doctor may use an anesthetic cream, or a cold pack, to numb your skin, or eye drops to numb your eyes before injecting onabotulinumtoxinA.

One brand or type of botulinum toxin cannot be substituted for another.

OnabotulinumtoxinA injection may help control your condition but will not cure it. It may take a few days or up to several weeks before you feel the full benefit of onabotulinumtoxinA injection. Ask your doctor when you can expect to see improvement, and call your doctor if your symptoms do not improve during the expected time.

Are there OTHER USES for this medicine?

OnabotulinumtoxinA injection is also sometimes used to treat other conditions in which abnormal muscle tightening causes pain, abnormal movements, or other symptoms. OnabotulinumtoxinA injection is also sometimes used to treat excessive sweating of the hands, many types of wrinkles of the face, tremor (uncontrollable shaking of a part of the body), and anal fissures (a split or tear in the tissue near the rectal area). The medication is also sometimes used to improve the ability to move in children with cerebral palsy (condition that causes difficulty with movement and balance). Talk to your doctor about the risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before receiving onabotulinumtoxinA injection,

  • tell your doctor and pharmacist if you are allergic to onabotulinumtoxinA, abobotulinumtoxinA (Dysport), incobotulinumtoxinA (Xeomin), prabotulinumtoxinA-xvfs (Jeuveau), or rimabotulinumtoxinB (Myobloc). Also, tell your doctor if you are allergic to any other medications or any of the ingredients in onabotulinumtoxinA injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: certain antibiotics such as amikacin, clindamycin (Cleocin), colistimethate (Coly-Mycin), gentamicin, kanamycin, lincomycin (Lincocin), neomycin, polymyxin, streptomycin, and tobramycin; anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven); antihistamines; aspirin and other nonsteroidal anti-inflammatory medications (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); heparin; medications for allergies, colds, or sleep; muscle relaxants; and platelet inhibitors such as clopidogrel (Plavix), dipyridamole (Persantine, in Aggrenox), prasugrel (Effient), and ticlopidine (Ticlid). Also tell your doctor if you have received injections of any botulinum toxin product including abobotulinumtoxinA (Dysport), incobotulinumtoxinA (Xeomin), prabotulinumtoxinA-xvfs (Jeuveau), or rimabotulinumtoxinB (Myobloc) within the past four months. Your doctor may need to change the doses or schedule of your medications or monitor you carefully for side effects. Many other medications may also interact with onabotulinumtoxinA, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
  • tell your doctor if you have swelling or other signs of infection or weakness in the area where onabotulinumtoxinA will be injected. Your doctor will not inject the medication into an area that is infected or weak.
  • if you will be receiving onabotulinumtoxinA injection to treat urinary incontinence, tell your doctor if you have a urinary tract infection (UTI), which may include symptoms such as pain or burning when you urinate, frequent urination, or fever; or if you have urinary retention (inability to fully empty the bladder) and do not regularly empty your bladder with a catheter. Your doctor will probably not treat you with onabotulinumtoxinA injection.
  • tell your doctor if you have ever had any side effect from any botulinum toxin product, or eye or face surgery, if you have or have ever had bleeding problems; seizures; hyperthyroidism (a condition that occurs when the thyroid gland produces too much thyroid hormone), diabetes, or lung or heart disease.
  • if you will be receiving onabotulinumtoxinA injection to treat wrinkles, your doctor will examine you to see if the medication is likely to work for you. OnabotulinumtoxinA injection may not smooth your wrinkles or may cause other problems if you have drooping eyelids; trouble raising your eyebrows; or any other change in the way your face normally looks.
  • if you are 65 years and older and will be receiving onabotulinumtoxinA (Botox Cosmetic) injection to temporarily smooth crow's feet, forehead lines, or frown lines, you should know that this treatment has not worked as well for older adults compared to adults younger than 65 years of age.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while receiving onabotulinumtoxinA injection, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving onabotulinumtoxinA injection.
  • you should know that onabotulinumtoxinA injection may cause loss of strength or muscle weakness all over the body or impaired vision. If you have any of these symptoms, do not drive a car, operate machinery, or do other dangerous activities.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What SIDE EFFECTS can this medicine cause?

OnabotulinumtoxinA injection may cause side effects. Ask your doctor which side effects you are most likely to experience, since some side effects may occur more often in the part of the body where you received the injection. Tell your doctor if any of these symptoms are severe or do not go away:

  • pain, tenderness, swelling, redness, bleeding, or bruising in the place where you received the injection
  • tiredness
  • neck pain
  • headache
  • drowsiness
  • muscle pain, stiffness, tightness, weakness, or spasm
  • pain or tightness in the face or neck
  • dry mouth
  • nausea
  • constipation
  • anxiety
  • sweating from parts of the body other than the underarms
  • cough, sneezing, fever, nasal congestion, or sore throat

    Some side effects can be serious. If you experience any of these symptoms, or those listed in the IMPORTANT WARNING section, at any time during the first several weeks after your treatment, call your doctor immediately or get emergency medical treatment:

  • double, blurred, or decreased vision
  • eyelid swelling
  • vision changes (such as light sensitivity or blurred vision)
  • dry, irritated, or painful eyes
  • difficulty moving the face
  • seizures
  • irregular heartbeat
  • chest pain
  • pain in the arms, back, neck, or jaw
  • shortness of breath
  • fainting
  • dizziness
  • rash
  • hives
  • itching
  • swelling of the hands, feet, ankles, or lower legs
  • cough, coughing up mucus, fever, or chills
  • inability to empty your bladder on your own
  • pain or burning when urinating or frequent urination
  • blood in urine
  • fever

OnabotulinumtoxinA injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose usually do not appear right after receiving the injection. If you received too much onabotulinumtoxinA or if you swallowed the medication, tell your doctor right away and also tell your doctor if you experience any of the following symptoms during the next several weeks:

  • weakness
  • difficulty moving any part of your body
  • difficulty breathing
  • difficulty swallowing

What OTHER INFORMATION should I know?

Keep all appointments with your doctor.

Ask your pharmacist any questions you have about onabotulinumtoxinA injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS® Patient Medication Information™. © Copyright, 2024. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: June 15, 2021.
AHFS® Patient Medication Information™. © Copyright, 2024
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