Comparative Pharmacology
Head-to-head clinical analysis: DESLORATADINE versus PROMETHAZINE VC W CODEINE.
Head-to-head clinical analysis: DESLORATADINE versus PROMETHAZINE VC W CODEINE.
DESLORATADINE vs PROMETHAZINE VC W/ CODEINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Desloratadine is a long-acting tricyclic histamine antagonist selective for the H1 receptor, inhibiting histamine release from mast cells and basophils. It reduces allergic inflammation by decreasing cytokine and chemokine release.
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.
5 mg orally once daily.
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
moderateDesloratadine + Venlafaxine
"The risk or severity of adverse effects can be increased when Desloratadine is combined with Venlafaxine."
Clinical Note
moderateDesloratadine + Nefazodone
"The risk or severity of adverse effects can be increased when Desloratadine is combined with Nefazodone."
Clinical Note
moderateDesloratadine + Stiripentol
"The risk or severity of adverse effects can be increased when Desloratadine is combined with Stiripentol."
Clinical Note
moderateTerminal half-life 27 hours (range 21–30 h) in healthy adults; supports once-daily dosing.
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.
Primarily renal (87% as metabolites, ~41% unchanged) and fecal (~9%). Metabolized to active 3-hydroxydesloratadine.
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
Desloratadine + Fesoterodine
"The serum concentration of the active metabolites of Fesoterodine can be increased when Fesoterodine is used in combination with Desloratadine."