What is Myobloc (Botulinum Toxin Type B)?

RimabotulinumtoxinB (Myobloc), also called botulinum toxin type B, is made from the bacteria that causes botulism. Botulinum toxin blocks nerve activity in the muscles, causing a temporary reduction in muscle activity.
Myobloc is used to treat cervical dystonia (severe spasms in the neck muscles).
Myobloc may also be used for other purposes not listed in this medication guide.

What is the most important information I should know about Myobloc (Botulinum Toxin Type B)?

The botulinum toxin contained in this medication can spread to other body areas beyond where it was injected. This has caused serious life-threatening side effects in some people receiving botulism toxin injections, even for cosmetic purposes.
Call your doctor at once if you have drooping eyelids, vision problems, severe muscle weakness, loss of bladder control, or trouble breathing, talking, or swallowing. Some of these effects can occur up to several weeks after a botulinum toxin injection.
Do not seek botulinum toxin injections from more than one medical professional at a time. If you switch healthcare providers, be sure to tell your new provider how long it has been since your last botulinum toxin injection.
Using this medication more often than prescribed will not make it more effective and may result in serious side effects.
You should not receive this medication if you are allergic to botulinum toxin, or if you have a skin infection in the area where the medicine will be injected.
Before receiving a botulinum toxin injection, tell your doctor if you have ALS ( Lou Gehrig’s disease), myasthenia gravis, or Lambert-Eaton syndrome.
The effects of a botulinum toxin injection are temporary. Your symptoms may return completely within 3 months after an injection. After repeat injections, it may take less and less time before your symptoms return, especially if your body develops antibodies to the botulinum toxin.

What should I discuss with my healthcare provider before taking Myobloc (Botulinum Toxin Type B)?

You should not receive this medication if you are allergic to botulinum toxin, or if you have a skin infection in the area where the medicine will be injected. Tell your doctor if you have ever had a side effect after receiving botulinum toxin in the past.
If you have any of these other conditions, you may need a dose adjustment or special tests:

amyotrophic lateral sclerosis (ALS, or “Lou Gehrig’s disease”)
myasthenia gravis
Lambert-Eaton syndrome
a breathing problem such as asthma or emphysema
problems with swallowing
bleeding problems
if you are planning to have surgery; or
if you have ever received other botulinum toxin injections such as Botox or Dysport (especially in the last 4 months)

Myobloc is made using human plasma (part of the blood) and may contain viruses and other infectious agents that can cause disease. Although donated human plasma is screened, tested, and treated to reduce the risk of it containing anything that could cause disease, there is still a small possibility it could transmit disease. Talk with your doctor about the risks and benefits of using this medication.
FDA pregnancy category C. It is not know whether botulinum toxin is harmful to an unborn baby. Before you receive this medication, tell your doctor if you are pregnant or plan to become pregnant during treatment.
It is not known whether botulinum toxin passes into breast milk or if it could harm a nursing baby. Do not receive this medication without telling your doctor if you are breast-feeding a baby.

Myobloc Side Effects

What are the possible side effects of Myobloc (Botulinum Toxin Type B)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
The botulinum toxin contained in this medication can spread to other body areas beyond where it was injected. This has caused serious life-threatening side effects in some people receiving botulism toxin injections, even for cosmetic purposes.
Call your doctor at once if you have any of these serious side effects, some of which can occur up to several weeks after an injection:

trouble breathing, talking, or swallowing
hoarse voice, drooping eyelids
unusual or severe muscle weakness (especially in a body area that was not injected with the medication)
loss of bladder control
problems with vision; or
chest pain

Less serious side effects may include:

pain or muscle weakness near where the medicine was injected
headache, joint or back pain
dry mouth, nausea, upset stomach
fever, cough, sore throat, flu symptoms
pain or stiffness in your neck; or
dizziness, drowsiness, anxiety

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Myobloc Interactions

What other drugs affect Myobloc (Botulinum Toxin Type B)?

Other drugs such as cold or allergy medicines, muscle relaxers, sleeping pills, bronchodilators, bladder or urinary medications, and irritable bowel medications can increase some of the side effects of Myobloc. Tell your doctor if you regularly use any of these medicines.
Tell your doctor about all other medicines you use, especially:

an antibiotic such as amikacin (Amikin), gentamicin (Garamycin), kanamycin (Kantrex), neomycin (Mycifradin, Neo-Fradin, Neo-Tab), paromomycin (Humatin, Paromycin), streptomycin, tobramycin (Nebcin, Tobi)

This list is not complete and other drugs may interact with Myobloc. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

What should I avoid while taking Myobloc (Botulinum Toxin Type B)?

Myobloc may impair your vision or depth perception. Be careful if you drive or do anything that requires you to be able to see clearly.

Myobloc Dosage

How should I take Myobloc (Botulinum Toxin Type B)?

This medication is injected into a muscle. A doctor, nurse, or other healthcare provider will give you this injection. Myobloc injections should be spaced at least 3 months apart.
Your injection may be given into more than one area at a time, depending on the condition being treated.
The effects of a botulinum toxin injection are temporary. Your symptoms may return completely within 3 months after an injection. After repeat injections, it may take less and less time before your symptoms return, especially if your body develops antibodies to the botulinum toxin.
Do not seek botulinum toxin injections from more than one medical professional at a time. If you switch healthcare providers, be sure to tell your new provider how long it has been since your last botulinum toxin injection.
Using this medication more often than prescribed will not make it more effective and may result in serious side effects.

What happens if I overdose on Myobloc (Botulinum Toxin Type B)?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Overdose symptoms may not appear right away, but can include muscle weakness, trouble swallowing, and weak or shallow breathing.

What happens if I miss a dose of Myobloc (Botulinum Toxin Type B)?

Since botulinum toxin has a temporary effect and is given at widely spaced intervals, missing a dose is not likely to be harmful.
Edited from everydayhealth.com

Botulinum Toxin Type B Myobloc

Myobloc (Botulinum Toxin Type B)