Comparative Pharmacology
Head-to-head clinical analysis: OXYMORPHONE HYDROCHLORIDE versus SYNALGOS DC A.
Head-to-head clinical analysis: OXYMORPHONE HYDROCHLORIDE versus SYNALGOS DC A.
OXYMORPHONE HYDROCHLORIDE vs SYNALGOS-DC-A
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Oxymorphone is a semi-synthetic opioid agonist that binds to mu-opioid receptors in the central nervous system, inhibiting ascending pain pathways and altering pain perception and response. It also has affinity for kappa and delta opioid receptors.
SYNALGOS-DC-A contains dihydrocodeine, which is a semisynthetic opioid agonist; aspirin, a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes; and caffeine, a central nervous system stimulant. Dihydrocodeine binds to mu-opioid receptors in the central nervous system to produce analgesia. Aspirin irreversibly acetylates COX-1 and COX-2, reducing prostaglandin synthesis. Caffeine enhances analgesia via adenosine receptor antagonism and possibly by increasing drug absorption.
Initial: 1 mg IV/IM every 3-4 hours as needed for moderate to severe pain; titrate to effect. For patient-controlled analgesia (PCA), 0.5 mg IV loading dose, then 0.25-0.5 mg every 6-15 minutes with lockout. Rectal suppository: 5 mg every 4-6 hours.
1-2 capsules orally every 4-6 hours as needed for pain; each capsule contains dihydrocodeine bitartrate 16 mg, acetaminophen 356.4 mg, and caffeine 30 mg.
None Documented
None Documented
Terminal elimination half-life: 7-9 hours (range 4-12 h in elderly/renal impairment). Clinically, steady-state achieved within 24-36 hours.
Propoxyphene: 6-12 hours; norpropoxyphene: 30-36 hours; clinical context: prolonged with hepatic impairment, age >60 years, and renal dysfunction; accumulation of norpropoxyphene may cause cardiotoxicity
Primarily renal (90% as parent drug and metabolites); <1% fecal. Unchanged oxymorphone accounts for ~30% of urinary recovery.
Renal: ~70-80% as free and conjugated propoxyphene; norpropoxyphene is renally eliminated; biliary: 10-20%; fecal: <10%
Category C
Category C
Opioid Analgesic
Opioid Analgesic