Merck Manual

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Skeletal Muscle Relaxants

Skeletal Muscle Relaxants

Drug

Dosage

Methocarbamol

Dogs, cats: 44 mg/kg, IV, up to 330 mg/kg/day for tetanus or strychnine poisoning; 132 mg/kg/day, PO, divided bid-tid

Horses: 4.4–5.5 mg/kg, IV

Guaifenesin

Dogs: 44–88 mg/kg, IV

Horses, ruminants: 66–132 mg/kg, IV

Diazepam

Cats: 2–5 mg, PO, tid, for urethral obstruction

Dantrolene

Horses: 15–25 mg/kg, slow IV, qid; 2 mg/kg/day, PO, for prevention of exertional rhabdomyolysis

Swine: 3.5 mg/kg, IV

Phenytoin

Horses: 6–8 mg/kg/day, PO, increase by 1 mg/kg every 3 days until rhabdomyolysis is prevented or the horse appears sedated