Muscle Relaxants

Why are muscle relaxants used?

A muscle relaxant is type of drug that can be used to reduce muscle spasms. A muscle spasm is an involuntary contraction of a muscle or a group of muscles. Muscle spasms are thought be caused by a protective reaction to tissue damage, which reduces range of movement and thus the risk of further damage. Muscle relaxants are often prescribed in an attempt to improve the initial limitations in range of motion from muscle spasm and to disrupt the pain-spasm-pain cycle. By limiting muscle spasm and improving range of motion the patient is more likely to be able to undertake therapeutic exercises.

How do muscle relaxants work?

It is still not clear how all muscle relaxants work. However, there is evidence to suggest that some muscle relaxants work by dampening down some of the nerve signals travelling down to the muscles. Some drugs may block the signals very close to the muscle itself, whilst others are more likely to dampen the signals at the level of the spinal cord and brain.

What are the side effects of muscle relaxants?

Every drug has possible side effects and so it is important to talk with your doctor or pharmacist about possible side effects before taking a new medication. It is important to remember that side effects will depend on the type of muscle relaxant you are taking. However, some of the more common side effects can include:

• Dizziness
• Drowsiness
• Double vision or blurred vision
• Light headedness
• Dry mouth

Less common side effects can include:

• Stomach cramps
• Pain
• Nausea & vomiting & diarrhoea
• Restlessness
• Irritability
• Sleep problems

What drugs are classified as muscle relaxants?

Carisoprodol (Soma)

Chlorzoxazone (Parafon Forte DSC)

Cyclobenzaprine (Flexeril)

Methocarbamol (Robaxin)

Metaxalone (Skelaxin)

Orphenadrine (Norflex)