Botulinum toxin (Botox)

Other names: Dysport, Xeomin

Botulinum toxin is a drug that is used to treat spasticity and spasms and bladder symptoms in multiple sclerosis.

Botulinum toxin is an extremely potent poison, made by the bacterium Clostridium botulinum. Its therapeutic use is now recognised in a range of symptoms, and it was first used to treat spasticity in MS in 1990. There are several different types of the toxin, with botulinum toxin A being the one most frequently used in MS.

What is botulinum toxin used for in MS?

In small, therapeutic doses injections of botulinum toxin can be used to treat several symptoms in MS. It can be injected into individual muscles to prevent the nerve messages that cause spasticity and spasms. It can be used to treat bladder symptoms when spasms in the muscle of the bladder wall cause urgency and incontinence. There is also some evidence to suggest that it may help with some types of tremor associated with MS.

How do I take botulinum toxin?

Botulinum toxin is injected. As the drug is so potent, and a misplaced application could lead to the loss of function or other complications, injections have to be delivered by a professional trained in the technique. As a treatment for MS, botulinum toxin is only available at specialist centres in the UK.

What side effects could I get with botulinum toxin?

The medicinal use of botulinum toxin is generally well tolerated and causes few side effects. As it can potentially interact with other medications, it is important to discuss all of your medicines with your health professionals when considering botulinum toxin treatment.

High doses of botulinum toxin can result in the muscle affected being completely (although not permanently) paralysed. Lower doses may be given in order to allow some muscle movement to continue. In the case of botox for bladder incontinence, this can mean you gain more control over bladder leakage.

How does botulinum toxin work?

Botulinum toxin is injected into a muscle and works by blocking the electrical messages from a nerve being transmitted to a muscle. Therefore it causes muscle paralysis, weakness and relaxation.

The effects of an injection with botulinum toxin last for several months, exactly how long depends on where it has been injected and what symptom it is being used for. The effect wears off when the damaged nerve ends regrow and start sending messages again, at this point the injections can be repeated.

Find out more

Snow BJ, et al.
Treatment of spasticity with botulinum toxin: a double-blind study.
Annals of Neurology 1990;28(4):512-515.
Summary (link is external)
Kalsi V, et al.
Botulinum injections for the treatment of bladder symptoms of multiple sclerosis.
Annals of Neurology 2007;62(5):452-457.
Summary (link is external)
Cruz F, et al.
Efficacy and safety of onabotulinumtoxinA in patients with urinary incontinence due to neurogenic detrusor overactivity: a randomised, double-blind, placebo-controlled trial.
European Urology 2011;60(4):742-750.
Summary (link is external)
Van Der Walt A, et al.
A double-blind, randomized, controlled study of botulinum toxin type A in MS-related tremor.
Neurology 2012;79(1):92-99.
Summary (link is external)
Tullman M, et al.
Low-dose onabotulinumtoxinA improves urinary symptoms in noncatheterizing patients with MS
Neurology August 14, 2018; 91 (7)
Summary (link is external)
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