Comparative Pharmacology
Head-to-head clinical analysis: ORPHENADRINE CITRATE versus ROBAXIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORPHENADRINE CITRATE versus ROBAXIN.
ORPHENADRINE CITRATE vs ROBAXIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Orphenadrine citrate is a centrally acting muscle relaxant with anticholinergic properties. Its exact mechanism of action is not fully understood, but it is believed to exert its effects by blocking muscarinic acetylcholine receptors and possibly by acting as an NMDA receptor antagonist. It may also have local anesthetic and antihistaminic properties.
Centrally acting muscle relaxant; depresses polysynaptic reflexes at spinal cord and supraspinal levels, possibly via glycine receptor agonism and GABAergic modulation.
100 mg orally twice daily. Maximum: 250 mg/day.
1500 mg orally 4 times daily, or 750 mg orally every 4 hours as needed. Maximum 6 g/day. For IV use: 1 g (10 mL) as a single intravenous injection or infusion.
None Documented
None Documented
Terminal elimination half-life is approximately 14 hours (range 11–20 hours) in adults; may be prolonged in elderly or hepatic impairment.
1-2 hours in adults; clinically, multiple daily dosing required to maintain effect.
Primarily renal excretion of metabolites; less than 10% excreted unchanged. Also undergoes biliary excretion with fecal elimination of conjugates.
Renal excretion of metabolites accounts for 99% of elimination; <1% excreted as unchanged drug in urine.
Category A/B
Category C
Skeletal Muscle Relaxant
Skeletal Muscle Relaxant