Class: Centrally Acting Skeletal Muscle Relaxant
Dosage Forms. Tablet: 500 mg, 750 mg
Common FDA Label Indication, Dosing, and Titration.
1. Musculoskeletal pain: 1500 mg po qid × 48-72 h, then may titrate to 750 mg po q4h, or 1500 mg po tid or 1000 mg po qid
Off-Label Uses. None
MOA. The mechanism of action of methocarbamol in humans has not been established, but may be due to general central nervous system (CNS) depression. It has no direct action on the contractile mechanism of striated muscle, the motor end plate, or the nerve fiber.
Drug Characteristics: Methocarbamol
Medication Safety Issues: Methocarbamol
Drug Interactions: Methocarbamol
Adverse Reactions: Methocarbamol
Efficacy Monitoring Parameters. Reduction in pain and muscle spasms.
Toxicity Monitoring Parameters. Seek medical attention if idiosyncratic symptoms such as extreme weakness, transient quadriplegia, dizziness, and confusion occur within minutes or hours after first dose; vital signs.
Key Patient Counseling Points. Patients should avoid activities requiring mental alertness or coordination until drug effects are known, as drug may cause dizziness or sedative effects.
Clinical Pearls. Methocarbamol is used for the relief of discomfort associated with acute, painful musculoskeletal conditions in adults and should be used for only short periods (up to 2 or 3 wk). Drug may color urine brown, black, or green. Injectable form available, used for spasticity associated with tetanus.