Onabotulinumtoxin A (BOTOX) is a powerful neurotoxin that temporarily blocks connections between the nerves and the muscles, resulting in short-term relaxation of the targeted muscle. Botox is administered by injection.
The efficacy and safety of BOTOX for the treatment of upper limb spasticity were evaluated in three randomized, multi-center, double-blind, placebo-controlled studies involving people who had upper-limb spasticity after stroke. In each of these studies, BOTOX showed benefit over placebo in treating upper limb spasticity.
The efficacy and safety of BOTOX for the treatment of overactive bladder in MS and other neurologic conditions were evaluated in two randomized, multi-center, double-blind, placebo-controlled studies involving people with MS or spinal cord injury who had previously been treated unsuccessfully with at least one anticholinergic medication. In each of the studies, BOTOX showed benefit over placebo in reducing episodes of incontinence.
Approval by the U.S. Food and Drug Administration (FDA)
BOTOX is approved by the FDA to treat upper limb spasticity in adults, to relieve increased muscle tone in elbow flexors (biceps), wrist flexors, and finger flexors. Upper limb spasticity can occur in MS as well as other disorders.
BOTOX is approved by the FDA to treat urinary incontinence resulting from overactivity of the bladder detrusor muscle caused by MS or other neurologic condition, in adults who have an inadequate response to anticholinergic medications or are unable to tolerate them.
- For upper limb spasticity: The dosage of BOTOX is based on the muscles that are affected, the severity of the spasticity in those muscles, a person’s prior response to treatment, and adverse events or complications the person has previously experienced. BOTOX treatment can be repeated when the effect of the previous treatment has worn off, but generally no sooner than 12 weeks after the previous injection.
- For overactive bladder: The recommended dosage is a maximum of 200 units per treatment. Re-injection may be considered when the clinical effect of the prior injection wears off (generally between 42-48 weeks, but no sooner than 12 weeks after the previous injection). The medication is injected into the bladder muscle using cystoscopy, a procedure that allows the doctor to visualize the interior of the bladder. Cystoscopy may require general anesthesia.
- The safety and effectiveness of BOTOX have not been evaluated in children less than 18 years of age.
- The safety and effectiveness of BOTOX for the treatment of lower limb spasticity have not been evaluated in adults or children.
- BOTOX has not been studied in pregnant women. Data from animal studies suggest that it may cause harm to the fetus. It should be used during pregnancy only if the potential benefit justified the potential risk to the fetus.
- It is not known if BOTOX is excreted in breast milk, so it should be used with caution by anyone who is breastfeeding.
- The FDA has issued a black box warning indicating that BOTOX (and all other Botulinum toxin products) may spread from the area of injection, causing serious side effects that can be life threatening—including problems swallowing, speaking, or breathing. These problems can occur within hours to weeks after an injection.
- People being treated for overactive bladder must not have a urinary tract infection when the injection is given. Appropriate preventive antibiotics should be given 1-3 days prior to treatment, on the treatment day, and 1-3 days after the treatment. People should also stop taking anti-plateles therapy at least 3 days before the injection, and thos who are taking an anti-coagulant therapy to be carefully managed in order to decrease the risk of bleeding.
- People with certain types of breathing problems prior to treatment with BOTOX may be at increased risk for complications caused by BOTOX.
- People who have problems swallowing prior to treatment with BOTOX may be at increased risk for complications caused by BOTOX.
In some cases, the effect of botulinum toxin may affect areas of the body far from the injection site, resulting in symptoms of botulism:
- Loss of strength and muscle weakness all over the body*
- Double vision*
- Blurred vision* and drooping eyelids
- Hoarseness or change or loss of voice
- Trouble saying words clearly
- Loss of bladder control*
- Trouble breathing
- Trouble swallowing *
- Do not take BOTOX if you are allergic to any of the ingredients in BOTOX or have had an allergic reaction to any Botulinum toxin product.
- Do not take BOTOX if you have a skin infection at the planned injection site.
- Tell your doctor about all the medications you take, including prescription and non-prescription medicines, vitamins and herbal products. And do not start any new medications until you have told your doctor about any recent Botox injections.
Possible Side Effects
The most common side effects in the clinical studies on upper limb spasticity included pain in the arms, fatigue*, muscle weakness*, nausea, and bronchitis. These problems are generally short-lasting but may last for months or longer.
The most common side effects in the clinical studies on overactice bladder included urinary tract infection, urinary retention, fatigue, and problems sleeping.
*Since it may be difficult to distinguish between certain common symptoms of MS and some side effects of BOTOX, be sure to consult your health care professional if an abrupt change of this type occurs.
BOTOX Patient Assistance Program:
1-800-44-BOTOX, Option 4