Comparative Pharmacology
Head-to-head clinical analysis: PHENERGAN VC W CODEINE versus QDOLO.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PHENERGAN VC W CODEINE versus QDOLO.
PHENERGAN VC W/ CODEINE vs QDOLO
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Phenergan VC w/ Codeine combines codeine (opioid agonist, mu-receptor), promethazine (histamine H1 antagonist, anticholinergic, sedative), and phenylephrine (alpha-1 adrenergic agonist). Codeine is metabolized to morphine for analgesia and antitussive effects; promethazine suppresses cough via central nervous system depression; phenylephrine causes vasoconstriction to relieve congestion.
Tramadol is a centrally acting synthetic opioid analgesic. It binds to μ-opioid receptors and inhibits norepinephrine and serotonin reuptake.
1 to 2 teaspoonfuls (5-10 mL) orally every 4 to 6 hours as needed. Maximum 4 doses in 24 hours.
Oral: 50-100 mg every 4-6 hours as needed for pain; maximum 400 mg per day. Immediate-release tablets only. Extended-release formulations require different dosing and are not interchangeable.
None Documented
None Documented
Codeine: terminal half-life ~3 hours (range 2.5-4.5 h) in adults; extended in renal impairment. Promethazine: terminal half-life ~10-14 hours (range 7-20 h) in adults; prolonged in elderly and hepatic impairment.
Terminal elimination half-life approximately 2-4 hours in adults; prolonged to 4-6 hours in elderly and up to 12-16 hours in severe renal impairment (CrCl <30 mL/min)
Codeine: renal elimination of metabolites (codeine-6-glucuronide, norcodeine, morphine, morphine-3-glucuronide, morphine-6-glucuronide); ~90% excreted in urine, <10% in feces. Promethazine: renal and biliary elimination as metabolites and unchanged drug; ~70-80% in urine, <20% in feces.
Renal 90% (60% unchanged, 30% as glucuronide conjugate), fecal 10%
Category D/X
Category C
Opioid Agonist
Opioid Agonist