Muscle Relaxer Medications

Skeletal muscle relaxants (also called muscle relaxers, or antispastic medications) are used to relieve muscle stiffness, pain, spasms, and discomfort caused by strains, sprains, or other musculoskeletal conditions.

Muscle relaxants do not actually relax muscles. Rather, these medications work on the central nervous system to produce their relaxant effects.

The term "muscle relaxants" is very broad and comprises a wide range of medications with different indications and modes of action. Muscle relaxants are divided into two main categories: antispasmodic and antispasticity drugs.

In the United States these medications are available only with doctor's prescription.

Conditions treated with muscle relaxants

Muscle relaxers are often prescribed for the following diseases and conditions:

• Fibromyalgia
• Low back pain
• Neck pain
• Tension headaches
• Myofascial pain syndrome
• Nocturnal leg cramps
• Conditions associated with spasticity

Baclofen, dantrolene, and tizanidine are approved for treatment of spasticity. Spasticity is a state of increased muscular tone with exaggeration of the tendon reflexes.

Carisoprodol, cyclobenzaprine, metaxalone, methocarbamol, and orphenadrine are indicated for treatment of musculoskeletal disorders, causing tenderness and muscle spasms. Muscle spasm is defined as a sudden involuntary contraction of one or more muscle groups and is usually an acute condition associated with muscle strain (partial tear of a muscle) or sprain (partial or complete rupture of a ligament). The muscle spasm produces pain, which then produces more spasm.

Comparative efficacy

One clinical study found that carisoprodol is superior to diazepam in the treatment of low back pain.

Cyclobenzaprine and carisoprodol were compared in the treatment of acute thoracolumbar pain and spasm rated moderate to severe and of no longer than seven days duration. Both medications were effective, without significant differences in terms of efficacy. While 60% of study participants experienced side effects such as drowsiness or fatigue, and only 8% of patients from each group discontinued treatment.

It is not clear if cyclobenzaprine is better than diazepam in the treatment of musculoskeletal conditions. One meta-analysis of unpublished trials and two head-to-head trials found that cyclobenzaprine and diazepam are nearly equally effective. On the other hand, three other clinical studies found cyclobenzaprine is more effective than diazepam at least in the first week of treatment.

Side effects

Skeletal muscle relaxants can cause various side effects, including:

• Drowsiness
• Dizziness
• Sedation
• Fatigue
• Lack of alertness
• Blurred vision
• Nausea

Central nervous system side effects are the most common adverse effects. Serious side effects with muscle relaxatns occur rare. Carisoprodol has a potential for abuse and dependence because of its metabolite meprobamate, a federally controlled substance.

These medications (particularly carisoprodol, cyclobenzaprine, and diazepam) should be used with caution in persons driving motor vehicles or operating heavy machinery.

Price-RX.com offers you price comparison of the following muscle relaxers prescription drugs:

• Carisoprodol - is typically prescribed on a short-term basis and may be habit-forming
• Cyclobenzaprine (Generic Flexeril) can be used on a longer-term basis and actually has a chemical structure related to some antidepressant medications. Cyclobenzaprine can impair mental and physical function, and may lead to urinary retention in males with large prostates.
• Flexeril
• Skelaxin
• Watson Soma

Last Updated: January 2010