Comparative Pharmacology
Head-to-head clinical analysis: METHOCARBAMOL versus ROBAXISAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: METHOCARBAMOL versus ROBAXISAL.
METHOCARBAMOL vs ROBAXISAL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Methocarbamol is a centrally acting muscle relaxant whose exact mechanism of action is not fully understood. It is thought to produce skeletal muscle relaxation by depressing the central nervous system, possibly via general CNS depression, without directly affecting the neuromuscular junction or skeletal muscle fibers.
Methocarbamol is a centrally acting muscle relaxant whose exact mechanism is not fully understood, but it is believed to involve general central nervous system depression and inhibition of polysynaptic reflexes in the spinal cord. Aspirin inhibits cyclooxygenase enzymes (COX-1 and COX-2), reducing prostaglandin synthesis, which provides analgesic and anti-inflammatory effects, and also irreversibly inhibits platelet aggregation.
METHOCARBAMOL 1500 mg orally 4 times daily or 750 mg orally every 4 hours, or 1-3 g intravenously every 8 hours, not to exceed 3 g/day intravenously for more than 3 consecutive days.
Oral: 2 tablets (methocarbamol 750 mg / aspirin 650 mg) 4 times daily.
None Documented
None Documented
Clinical Note
moderateMethocarbamol + Fluticasone propionate
"The risk or severity of adverse effects can be increased when Methocarbamol is combined with Fluticasone propionate."
Clinical Note
moderateMethocarbamol + Venlafaxine
"The risk or severity of adverse effects can be increased when Methocarbamol is combined with Venlafaxine."
Clinical Note
moderateMethocarbamol + Nefazodone
"The risk or severity of adverse effects can be increased when Methocarbamol is combined with Nefazodone."
Clinical Note
moderateTerminal elimination half-life: 1-2 hours. Clinical context: short half-life necessitates frequent dosing (q6h) for sustained muscle relaxation.
Methocarbamol: 1.0–2.0 hours (prolonged in renal impairment); guaifenesin: approximately 1 hour.
Renal: primarily as glucuronide conjugates and unchanged drug (~50-70% as metabolites, <2% unchanged). Fecal: minimal, <2%. Biliary: not significant.
Methocarbamol: renal (primarily as glucuronide and sulfate conjugates, with <2% unchanged); guaifenesin: renal (metabolites, <1% unchanged). No significant biliary/fecal elimination.
Category A/B
Category C
Skeletal Muscle Relaxant
Skeletal Muscle Relaxant
Methocarbamol + Stiripentol
"The risk or severity of adverse effects can be increased when Methocarbamol is combined with Stiripentol."