Note: This document contains side effect information about rimabotulinumtoxinB. Some dosage forms listed on this page may not apply to the brand name Myobloc.
Summary
Common side effects of Myobloc include: dysphagia, dyspepsia, nausea, pain, and xerostomia. Other side effects include: asthenia, myasthenia, back pain, increased cough, and influenza. Continue reading for a comprehensive list of adverse effects.
Applies to rimabotulinumtoxinB: intramuscular solution.
Warning
Intramuscular route (Injectable)
Postmarketing reports indicate that the effects of rimabotulinumtoxinB and all botulinum toxin products may spread from the area of injection to produce symptoms consistent with botulinum toxin effects. These may include asthenia, generalized muscle weakness, diplopia, blurred vision, ptosis, dysphagia, dysphonia, dysarthria, urinary incontinence, and breathing difficulties. These symptoms have been reported hours to weeks after injection. Swallowing and breathing difficulties can be life threatening and there have been reports of death. The risk of symptoms is probably greatest in children treated for spasticity but symptoms can also occur in adults treated for spasticity and other conditions, particularly in those patients who have underlying conditions that would predispose them to these symptoms. In unapproved uses, including spasticity in children and adults, and in approved indications, cases of spread of effect have occurred at doses comparable to those used to treat cervical dystonia and at lower doses.
Serious side effects of Myobloc
Along with its needed effects, rimabotulinumtoxinB (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 rimabotulinumtoxinB:
More common
- Difficulty with swallowing
- infection
- neck pain
- uncontrolled twisting movements of the neck
Rare
- Difficulty with breathing or speaking
- muscle weakness
Incidence not known
- Cough
- dizziness
- fast heartbeat
- hives, itching, or skin rash
- large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
- puffiness or swelling of the eyelids or around the eyes, face, lips or tongue
- tightness in the chest
- unusual tiredness or weakness
Other side effects of Myobloc
Some side effects of rimabotulinumtoxinB 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
- belching
- 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
- cough
- difficulty with moving
- dizziness
- dry mouth
- flu-like syndrome
- headache
- heartburn or indigestion
- lack or loss of strength or energy
- muscle pain, stiffness, or weakness
- nausea
- pain, swelling, or redness in the joints
- stomach discomfort, upset, or pain
Other side effects of Myobloc
Some side effects of rimabotulinumtoxinB 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 rimabotulinumtoxinB: injectable solution, intramuscular solution.
General
The most commonly reported adverse events have included dry mouth, dysphagia, dyspepsia, and injection site pain.[Ref]
Gastrointestinal
Most case reports of dry mouth or dysphagia were reported as mild or moderate, however, these were the most frequent adverse events resulting in treatment discontinuation. An increased incidence of dysphagia occurred with an increased dose in the sternocleidomastoid muscle; an increasing incidence of dry mouth was associated with dose-related increases in doses injected into the splenius capitis, trapezius, and sternocleidomastoid muscles.
Gastrointestinal disorder, vomiting, glossitis, stomatitis, and tooth disorder were reported in greater than 2% of patients.[Ref]
Very common (10% or more): Dry mouth (up to 39%), dysphagia (up to 25%)
Common (1% to 10%): Dyspepsia, nausea, dental carries
Frequency not reported: Gastrointestinal disorder, vomiting, glossitis, stomatitis, tooth disorder
Postmarketing reports: Constipation[Ref]
Respiratory
Common (1% to 10%): Increased cough, rhinitis, dysphonia
Frequency not reported: Dyspnea, lung disorder, pneumonia
Postmarketing reports: Aspiration pneumonia[Ref]
Dyspnea, lung disorder, and pneumonia were reported in greater than 2% of patients.[Ref]
Cardiovascular
Frequency not reported: Peripheral edema, edema, chest pain, vasodilation[Ref]
Chest pain, vasodilation, peripheral edema, and edema were reported in greater than 2% of patients.[Ref]
Local
Very common (10% or more): Injection site pain (up to 15%)[Ref]
Musculoskeletal
Common (1% to 10%): Arthralgia, back pain
Frequency not reported: Arthritis, joint disorder
Postmarketing reports: Exaggerated muscle weakness[Ref]
Arthritis and joint disorder were reported in greater than 2% of patients.[Ref]
Ocular
Common (1% to 10%): Blurred vision
Postmarketing reports: Abnormal accommodation, ptosis, dry eye, accomodation disorder[Ref]
Hypersensitivity
Frequency not reported: Allergic reaction[Ref]
Allergic reaction was reported in greater than 2% of patients.[Ref]
Nervous system
Very common (10% or more): Headache (up to 11%)
Common (1% to 10%): Torticollis, myasthenia, dizziness
Frequency not reported: Migraine, hyperesthesia, somnolence, taste perversion[Ref]
Migraine, hyperesthesia, somnolence, and taste perversion were reported in greater than 2% of patients.[Ref]
Dermatologic
Frequency not reported: Cyst, pruritus, ecchymosis
Postmarketing reports: Angioedema, urticaria, rash[Ref]
Cyst, ecchymosis, and pruritus was reported in greater than 2% of patients.[Ref]
Immunologic
Very common (10% or more): Infection (up to 15%)
Common (1% to 10%): Flu syndrome
Frequency not reported: Viral infection, antibodies against botulinum toxin b[Ref]
Viral infection and antibodies against botulinum toxin b were reported in greater than 2% of patients.[Ref]
Metabolic
Frequency not reported: Hypercholesterolemia[Ref]
Hypercholesterolemia was reported in greater than 2% of patients.[Ref]
Psychiatric
Frequency not reported: Anxiety, confusion[Ref]
Anxiety and confusion were reported in greater than 2% of patients.[Ref]
Other
Very common (10% or more): Neck pain related to cervical dystonia (up to 17%), pain (up to 13%)
Common (1% to 10%): Asthenia, accidental injury
Frequency not reported: Chills, malaise, fever, vertigo, otitis media, tinnitus, tremor[Ref]
Chills, malaise, fever, vertigo, otitis media, tinnitus, tremor were reported in greater than 2% of patients.[Ref]
Genitourinary
Urinary tract infection, cystitis, and vaginal moniliasis were reported in greater than 2% of patients.[Ref]
Frequency not reported: Urinary tract infection, cystitis, vaginal moniliasis[Ref]
Oncologic
Neoplasm was reported in greater than 2% of patients.[Ref]
Frequency not reported: Neoplasm[Ref]
