eMedExpert Home > Comparisons > Carisoprodol (Soma)

Muscle relaxants do not share many similarities other than their intended purpose. This makes it difficult to identify any one as the “best muscle relaxant”.

In a trial of cyclobenzaprine versus carisoprodol in patients with acute back pain and spasms there were no significant differences for pain, muscle stiffness, activity impairment, sleep impairment, tension, or relief scores compared to baseline. In this head-to-head trial dry mouth was more frequent with cyclobenzaprine (38% vs. 10%) and dizziness less frequent (8% vs. 26%). Withdrawal rates due to adverse events were equal (8%) (3).

In a double-blind study carisoprodol was found to be superior to diazepam in the treatment of patients with at least moderately severe low back pain and spasm of no longer than seven days duration.

The first RCT (80 people) found that carisoprodol significantly increased overall improvement compared with diazepam but found no significant difference in pain at 7 days (improvement rated as very good or excellent; 70% with carisoprodol v 45% with diazepam; pain on 100 mm visual analogue scale: 58 mm with carisoprodol v 48 mm with diazepam; P values not reported in the review)

Carisoprodol was more effective than diazepam in overall relief of acute LBP (70% vs. 45%)

In this head-to-head trial, the overall incidence of adverse reactions was higher in the diazepam treated group but was not of statistical significance.

In an attempt to determine the mechanism of action of carisoprodol (Soma) in the treatment of low back pain, a double blind study was carried out comparing its effectiveness to that of a sedative control, butabarbital, and a placebo in the treatment of 48 laborers with acute lumbar strain and spasm [4].

Carisoprodol produced significantly greater relief of pain, spasm, tension, and limitation of normal daily activities than butabarbital when evaluated by finger to floor testing. The study suggests that carisoprodol also exerts muscle relaxant activity.

• Carisoprodol (Soma) Facts

• 1. Boyles W, Glassman J, Soyka J. Management of acute musculoskeletal conditions: thoracolumbar strain or sprain. A double-blind evaluation comparing the efficacy and safety of carisoprodol with diazepam. Today's Ther Trends 1983; 1: 1-16.
• 2. Rollings H. Management of acute musculoskeletal conditions-thoracolumbar strain or sprain: a double-blind evaluation comparing the efficacy and safety of carisoprodol with cyclobenzaprine hydrochloride. Curr Ther Res 1983; 34: 917-28.
• 3. Rollings HE, Glassman JM, Soyka JP. Management of acute musculoskeletal conditions - Thoracolumbar strain or sprain: A double-blind evaluation comparing the efficacy and safety of carisoprodol with cyclobenzaprine hydrochloride. Curr Ther Res. 1983;34(6):917-928.
• 4. Hindle TH 3rd. Comparison of carisoprodol, butabarbital, and placebo in treatment of the low back syndrome. Calif Med. 1972 Aug;117(2):7-11. PubMed

Published: March 31, 2008
Last updated: December 23, 2011