Comparative Pharmacology
Head-to-head clinical analysis: HYDROXYZINE versus PROMETHAZINE VC W CODEINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HYDROXYZINE versus PROMETHAZINE VC W CODEINE.
HYDROXYZINE vs PROMETHAZINE VC W/ CODEINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydroxyzine is a first-generation antihistamine that acts as a competitive antagonist at histamine H1 receptors in the gastrointestinal tract, blood vessels, and respiratory tract. It also exhibits sedative, anxiolytic, and antiemetic properties, possibly through central nervous system depression and anticholinergic effects.
Codeine is a prodrug converted to morphine, which acts as a mu-opioid receptor agonist inhibiting ascending pain pathways and altering pain perception. Promethazine is a phenothiazine derivative that antagonizes histamine H1 receptors, suppresses cough reflex via central action, and has anticholinergic, sedative, and antiemetic effects. Phenylephrine is a selective alpha-1 adrenergic receptor agonist causing vasoconstriction of nasal blood vessels, reducing congestion.
25-100 mg orally 3-4 times daily; 50-100 mg IM every 4-6 hours as needed. Maximum oral dose: 600 mg/day in divided doses.
1-2 tablets orally every 4-6 hours as needed for cough and congestion. Maximum 12 tablets in 24 hours.
None Documented
None Documented
Clinical Note
moderateHydroxyzine + Venlafaxine
"The risk or severity of adverse effects can be increased when Hydroxyzine is combined with Venlafaxine."
Clinical Note
moderateHydroxyzine + Nefazodone
"The risk or severity of adverse effects can be increased when Hydroxyzine is combined with Nefazodone."
Clinical Note
moderateHydroxyzine + Mifepristone
"Hydroxyzine may increase the QTc-prolonging activities of Mifepristone."
Clinical Note
moderateHydroxyzine + Fesoterodine
Terminal elimination half-life: 14-25 hours (mean ~20 h). In elderly or hepatic impairment, may be prolonged; antihistamine effect persists beyond half-life due to active metabolite.
Promethazine: 9-16 hours (range 7-20 hours) in adults; codeine: 2.5-3.5 hours (terminal) with clinical considerations for prolonged effects in hepatic impairment and CYP2D6 poor metabolizers.
Renal: approximately 70% as metabolites, less than 1% unchanged. Fecal/biliary: minor. Cetirizine (active metabolite) also renally eliminated.
Renal: 70-80% as unchanged promethazine and metabolites (including codeine and its glucuronides); biliary/fecal: 10-20%.
Category A/B
Category A/B
Antihistamine
Antihistamine / Antiemetic
"The serum concentration of the active metabolites of Fesoterodine can be increased when Fesoterodine is used in combination with Hydroxyzine."