Detailed Information
Carisoprodol is a a centrally-acting skeletal muscle relaxant.
This drug is an isopropyl derivative of meprobamate. This medicine
is used, along with rest and physical therapy, to treat injuries
and other painful muscular conditions. Carisoprodol works by blocking
nerve impulses that are sent to your brain. With an average dose
of 350 mg, four times per day, drowsiness and drowsiness are the
main side effects.
Off-label uses:
- Low back pain (2, 3)
- Fibromyalgia (1)
History
On June 1st 1959 several American pharmacologist convened at Wayne
State University, Detroit, MI to discuss a new drug. The drug, originally
thought to have antiseptic properties, was found to have central
muscle relaxing properties. It had been developed by Dr. Frank M.
Berger at Wallace laboratories and had been named carisoprodol.
The misuse and abuse of meprobamate and other muscle relaxing drugs
was an item of great concern in the 1950s and 1960s 3-5 . Carisoprodol
i was developed in the 1950s on the basis of meprobamate, hoping
that it would have better muscle-relaxing properties, less abuse-potential,
and less risk of overdose than meprobamate 18 . The substitution
of one hydrogen atom with an isopropyl group on one of the carbamyl
nitrogens was intended to yield a molecule with new pharmacological
properties.
Onset of action: 30 min.
Duration of action: 4 to 6 hr.
Carisoprodol for fibromyalgia
The results of double blind trial indicated that combination of
carisoprodol, paracetamol and caffeine are effective in the treatment
of fibromyalgia.
Treatment with carisoprodol, paracetamol and caffeine gave statistically
significant improvement after treatment for pain, for sleep quality
and for the general feeling of sickness. In the active treatment
group increased pressure pain threshold after eight weeks was found
at 70% of the sites measured, while the pressure pain threshold
was increased at only 30% of the sites in the placebo group. In
the placebo group improvement was found for the pain and sleep quality.
This improvement may in part be due to the large amounts of extra
medication in placebo group (1).
Carisoprodol versus Butabarbital
This results of a double-blind study have shown that carisoprodol
is significantly more effective than butabarbital or placebo in
producing improvement of all factors rated in treatment of the low
back syndrome. The effects of carisoprodol are not due solely to
sedative action, but are also related to its muscle relaxant activity
(3).
The study was carried out to determine the effectiveness of carisoprodol
in the treatment of the low back syndrome, and to test whether this
drug would produce any greater effect than an active sedative control
(butabarbital). 48 Mexican migrant farm laborers with acute lumbar
strain and spasm were given either carisoprodol 350 mg, butabarbital
15 mg, or placebo, four times daily for four days, and then were
rated on pertinent symptoms, the degree of limitation of motion,
and overall improvement. In the 43 patients who could be statistically
analyzed, carisoprodol was shown to be significantly more effective
than butabarbital or placebo in producing improvement.
Carisoprodol versus Cyclobenzaprine
Cyclobenzaprine and carisoprodol were compared in the treatment
of patients with acute thoracolumbar pain and spasm rated moderate
to severe and of no longer than seven days duration (4). Both drugs
were found to be effective, without significant differences between
the treatment groups. Significant improvements were noted in physician
rated mobility and in patients' visual analogue scores on follow
up days four and eight. While 60% of patients experienced adverse
effects in the form of drowsiness or fatigue, these differences
were not significantly different between groups, and only eight
percent of patients from each group discontinued treatment.
Dosage
Carisoprodol is most often taken therapeutically in doses of
350 mg p.o. up to 3 or 4 times per day. In clinical practice the
drug is, however, also ingested in doses of 700 mg up to 3 or 4
times per day.
