Myobloc Side Effects
Generic Name: botulinum toxin type b
Note: This document contains side effect information about botulinum toxin type b. Some of the dosage forms listed on this page may not apply to the brand name Myobloc.
Common side effects of Myobloc include: dysphagia, dyspepsia, nausea, pain, and xerostomia. Other side effects include: back pain, increased cough, influenza, and myasthenia. See below for a comprehensive list of adverse effects.
For the Consumer
Applies to botulinum toxin type b: intramuscular solution
Along with its needed effects, botulinum toxin type b (the active ingredient contained in Myobloc) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur while taking botulinum toxin type b:More common
- Difficulty with swallowing
- neck pain
- uncontrolled twisting movements of the neck
- Difficulty with breathing or speaking
- muscle weakness
Some side effects of botulinum toxin type b may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:More common
- Acid or sour stomach
- back pain
- bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
- difficulty with moving
- dry mouth
- flu-like syndrome
- heartburn or indigestion
- lack or loss of strength or energy
- muscle pain, stiffness, or weakness
- pain, swelling, or redness in the joints
- stomach discomfort, upset, or pain
Some side effects of botulinum toxin type b may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
For Healthcare Professionals
Applies to botulinum toxin type b: injectable solution
Cardiovascular side effects have included headache (up to 16%) and chest pain.[Ref]
Dermatologic side effects including pruritus have been reported in 2% of patients or less.[Ref]
Gastrointestinal side effects have included dysphagia (up to 25%), dyspepsia (up to 10%), nausea (up to 10%), and to a lesser extent (2% or less) vomiting, glossitis, stomatitis, and tooth disorder.[Ref]
Dry mouth is the most commonly reported adverse effect (occurring in up to 34% of patients). Other general side effects have included torticollis (up to 8%) and, to a lesser extent (2% or less), fever, chills, hernia, malaise, abscess, cyst, and neoplasm.[Ref]
Genitourinary side effects reported in 2% of patients or less have included urinary tract infection, cystitis, and vaginal moniliasis.[Ref]
Immunologic side effects have included infection (up to 19%) and flu syndrome (up to 9%). Other immunologic side effects reported to a lesser extent (2% or less) have included otitis media and viral infection.[Ref]
Local side effects including injection site pain have been reported (up to 16%).[Ref]
Musculoskeletal side effects have included neck pain related to cervical dystonia (up to 17%), torticollis (up to 8%), arthralgia (up to 7%), back pain (up to 7%), myasthenia (up to 6%), and asthenia (up to 6%). Other musculoskeletal side effects reported in 2% of patients or less have included arthritis and joint disorder.[Ref]
Nervous system side effects reported in 2% of patients or less have included anxiety, tremor, hyperesthesia, somnolence, confusion, pain related to cervical dystonia/torticollis, vertigo, and vasodilation.[Ref]
Respiratory side effects have included increased cough (up to 7%), rhinitis (up to 6%), and, to a lesser extent (2% or less), dyspnea, lung disorder, and pneumonia.[Ref]
Ocular side effects including a case of bilateral ptosis have been reported.[Ref]
1. "Product Information. Myobloc (botulinum toxin type B)" Elan Pharmaceuticals, S. San Francisco, CA.
2. "Product Information. Botox (botulinum toxin type A)" Allergan Inc, Irvine, CA.
3. Racette BA, Lopate G, Good L, Sagitto S, Perlmutter JS "Ptosis as a remote effect of therapeutic botulinum toxin B injection." Neurology 59 (2002): 1445-7
Some side effects of Myobloc may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.
More about Myobloc (botulinum toxin type b)
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- Support Group
- Pricing & Coupons
- En Español
- 2 Reviews – Add your own review/rating
- Drug class: skeletal muscle relaxants
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