Comparative Pharmacology
Head-to-head clinical analysis: ORPHENADRINE CITRATE ASPIRIN AND CAFFEINE versus ROBAXIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORPHENADRINE CITRATE ASPIRIN AND CAFFEINE versus ROBAXIN.
ORPHENADRINE CITRATE, ASPIRIN, AND CAFFEINE 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; aspirin is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis; caffeine is a central nervous system stimulant that antagonizes adenosine receptors.
Centrally acting muscle relaxant; depresses polysynaptic reflexes at spinal cord and supraspinal levels, possibly via glycine receptor agonism and GABAergic modulation.
1-2 tablets (orphenadrine citrate 50 mg, aspirin 770 mg, caffeine 60 mg per tablet) orally every 8-12 hours as needed; maximum 4 tablets per 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
Orphenadrine: ~14 hours (range 12-16 h); Aspirin: 2-3 h for low doses, 15-30 h for high/anti-inflammatory doses due to saturable metabolism; Caffeine: 3-6 h in adults, prolonged in liver disease.
1-2 hours in adults; clinically, multiple daily dosing required to maintain effect.
Orphenadrine: ~60% renal (metabolites, <8% unchanged), ~20% biliary/fecal; Aspirin: ~80-100% renal (salicylates, dose-dependent; alkaline urine increases excretion); Caffeine: ~1-3% renal (unchanged), main metabolites renal.
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