methocarbamol: clinical use

Prescribing considerations

• Confirm the indication is painful muscle tension in an adult.
• Review concurrent alcohol, opioids, sedatives, anticholinergics and psychotropic medicines for additive effects.
• Use caution with renal or hepatic impairment; hepatic disease may prolong elimination.
• Advise about drowsiness, dizziness and impairment of driving or machinery use.
• Methocarbamol can cause colour interference in tests for 5-HIAA and VMA.

Contraindications and cautions

• Hypersensitivity to methocarbamol or product excipients
• Comatose or pre-comatose states
• Central nervous system disorders
• Myasthenia gravis
• Epilepsy or a tendency to convulsions

Monitoring

• No routine laboratory monitoring is specified in the selected SmPCs.
• Assess clinical response, ongoing need and central nervous system adverse effects.
• Review promptly if allergic symptoms, syncope, seizures, confusion or significant cardiovascular symptoms occur.

Clinical pharmacology

Methocarbamol inhibits polysynaptic reflexes in spinal and subcortical centres. It is rapidly absorbed orally, has an approximate two-hour plasma half-life and is eliminated mainly through the kidneys after conjugation.

Formulation and product differences

• Both selected products are oral film-coated tablets.
• The neuraxpharm tablet contains lactose and has a score line for ease of swallowing only, not equal division.
• The Milpharm tablet is essentially sodium-free, contains no listed lactose and is supplied as an unscored tablet in a bottle.
• Neuraxpharm storage conditions vary by blister material; the Milpharm product requires no special storage conditions.

Tablet

Route: Oral

Strengths: 750 mg, 1500 mg