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Myobloc

Generic name: rimabotulinumtoxinBRIM-a-BOT-ue-LYE-num-TOX-in-BEE ]
Drug class: Skeletal muscle relaxants

Medically reviewed by Drugs.com on Dec 9, 2024. Written by Cerner Multum.

What is Myobloc?

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 in adults to treat abnormal head position and neck pain due from cervical dystonia.

Myobloc is also used in adults to treat chronic drooling (sialorrhea).

Myobloc may also be used for purposes not listed in this medication guide.

Myobloc side effects

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

The botulinum toxin contained in Myobloc can spread to other body areas beyond where it was injected. This has caused side effects in some people after receiving botulinum toxin injections, even for cosmetic purposes. Swallowing and breathing problems can be serious life-threatening, especially in children with certain muscle problems.

Call your doctor at once if you have any of these side effects (up to several hours or weeks after an injection):

Common side effects of Myobloc may include:

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.

Warnings

The botulinum toxin contained in Myobloc can spread to other body areas beyond where it was injected. This can cause serious life-threatening side effects.

Call your doctor at once if you have a hoarse voice, droopy 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.

Before taking this medicine

You should not be treated with Myobloc if you are allergic to it or to any other botulinum toxin injection, such as onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA, or if you have an infection in the area where the medicine will be injected.

Tell your doctor if you have ever had a side effect after receiving a botulinum toxin.

Tell your doctor if you have or have ever had:

Myobloc is made from donated human plasma and may contain viruses or other infectious agents. Donated plasma is tested and treated to reduce the risk of contamination, but there is still a small possibility it could transmit disease. Ask your doctor about any possible risk.

It is not known if Myobloc will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using Myobloc.

How is Myobloc given?

Myobloc is injected into a muscle or into a gland by a healthcare provider. Your doctor will determine when to receive the next dose.

Your injections may be given into more than one area at a time, depending on the condition being treated.

Your doctor may occasionally change your dose until your doctor determines the best dose.

Your doctor may need to check your progress on a regular basis, and your next dose may change based on your response to treatment.

Call your doctor if your symptoms do not improve, or if they get worse.

Do not receive 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 medicine more often than prescribed will not make it more effective and may result in serious side effects.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your Myobloc.

What happens if I overdose?

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, weak or shallow breathing, or loss of movement in any part of your body.

What should I avoid after receiving Myobloc?

Myobloc may impair your reactions and may cause weakness, loss of strength, or vision changes. Avoid driving or hazardous activity until you know how Myobloc will affect you.

What other drugs will affect Myobloc?

Tell your doctor about all your other medicines, especially:

This list is not complete and many other drugs may affect Myobloc. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Does Myobloc interact with my other drugs?

Enter medications to view a detailed interaction report using our Drug Interaction Checker.

Myobloc Biosimilars

Biosimilar and interchangeable products are biological products that are highly similar to and have no clinically meaningful differences from the reference product.

Reference products

These are biological products that have already been approved by the FDA, against which biosimilar products are compared. There is 1 for Myobloc.

Myobloc (rimabotulinumtoxinB) - Solstice NeuroSciences, LLC
Formulation type Strength
Single-Dose Vial 10,000 units/2 mL (5,000 units/mL)
Single-Dose Vial 2,500 units/0.5 mL
Single-Dose Vial 5,000 units/mL

Frequently asked questions

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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