What is Soma (carisoprodol)?

Soma (Carisoprodol): A Centrally Acting Muscle Relaxant with High Abuse Potential

Soma (carisoprodol) is a centrally acting muscle relaxant with substantial barbiturate-like properties that has high abuse potential and should only be used for short periods (up to 2-3 weeks) for acute, painful musculoskeletal conditions. 1, 2

Pharmacological Properties and Mechanism

• Carisoprodol is a centrally acting muscle relaxant with:
  • Barbiturate-like biological action
  • Central nervous system depressant effects
  • Anxiolytic properties
  • Rapid onset of action (within hours)
  • Effects lasting 4-6 hours 1
  • Metabolized to meprobamate, a Schedule IV controlled substance 3, 4

FDA-Approved Indications

• Relief of discomfort associated with acute, painful musculoskeletal conditions in adults
• Important limitation: Should only be used for short periods (up to 2-3 weeks) as:
  • Adequate evidence for prolonged use effectiveness is lacking
  • Acute painful musculoskeletal conditions are generally short-duration 2

Adverse Effects

Carisoprodol has numerous concerning adverse effects:

• Sedation (common and significant)
• Seizures
• Drug dependence and withdrawal
• Tachycardia
• Postural hypotension 1
• Central nervous system depression (particularly dangerous when combined with other CNS depressants) 1

Abuse and Addiction Potential

Carisoprodol has significant abuse potential:

• Classified as a controlled substance due to abuse and addiction risk
• FDA has reported escalating abuse in the past decade
• Commonly diverted medication 1
• Patients may request it by name, "lose" prescriptions, or use it chronically 5
• Patients with history of substance abuse are at higher risk for carisoprodol abuse 3

Withdrawal Considerations

• With prolonged use at high doses, carisoprodol leads to:
  • Tolerance
  • Dependence
  • Withdrawal symptoms
• Withdrawal can cause severe symptoms
• Critical safety note: Must be tapered slowly (over 4-9 days) rather than stopped abruptly 1

Perioperative Considerations

For patients on carisoprodol requiring surgery:

• Hold on day of operation
• If time permits, consider tapering off or switching to alternative agent before surgical procedures 1
• Avoid co-prescribing with opioids and benzodiazepines due to increased mortality risk 1

Efficacy Evidence

• In a 7-day randomized controlled trial, carisoprodol 250mg was more effective than placebo for acute muscle spasm of the lower back 6
• However, systematic reviews indicate limited evidence for long-term effectiveness 1

Clinical Warning Signs of Abuse

Be alert for patients:

• Requesting the drug by name
• Reporting "lost" prescriptions
• Using carisoprodol chronically
• Refusing equally effective but less mind-altering alternatives 5

Alternative Treatments

For musculoskeletal pain, consider these alternatives with better safety profiles:

• NSAIDs as first-line therapy
• Other skeletal muscle relaxants with lower abuse potential
• Non-pharmacological approaches (exercise therapy, mindfulness-based stress reduction) 7

Key Clinical Caution

Many physicians remain unaware of carisoprodol's abuse potential and its metabolism to meprobamate (a controlled substance). This lack of awareness contributes to inappropriate prescribing patterns and potential patient harm 3, 4.