Comparative Pharmacology
Head-to-head clinical analysis: LORATADINE versus PROMETHAZINE W CODEINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LORATADINE versus PROMETHAZINE W CODEINE.
LORATADINE vs PROMETHAZINE W/ CODEINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Loratadine is a long-acting tricyclic antihistamine with selective peripheral H1-receptor antagonist activity. It inhibits histamine-induced vasodilation and bronchoconstriction.
Codeine is a prodrug converted to morphine, a mu-opioid receptor agonist, which inhibits nociceptive transmission; promethazine is a phenothiazine derivative with H1-receptor antagonism, anticholinergic, and antiemetic effects.
10 mg orally once daily
10 mL (1 mg codeine, 6.25 mg promethazine per 5 mL) orally every 4-6 hours as needed for cough. Maximum: 60 mL per day. Do not exceed 5 days.
None Documented
None Documented
Loratadine: 8-14 hours (mean ~10 hours). Active metabolite descarboethoxyloratadine: 17-24 hours (mean ~20 hours). Clinically, duration supports once-daily dosing.
Clinical Note
moderateLoratadine + Fluticasone propionate
"The risk or severity of adverse effects can be increased when Loratadine is combined with Fluticasone propionate."
Clinical Note
moderateLoratadine + Teriflunomide
"The metabolism of Teriflunomide can be decreased when combined with Loratadine."
Clinical Note
moderateLoratadine + Haloperidol
"The metabolism of Haloperidol can be decreased when combined with Loratadine."
Clinical Note
moderateLoratadine + Sulfisoxazole
Promethazine: 10-19 hours (terminal). Codeine: 2.5-3.5 hours (terminal); prolonged in renal impairment.
Approximately 40% excreted in urine as metabolites (primarily descarboethoxyloratadine) and 40% in feces as metabolites; <1% excreted unchanged.
Promethazine: renal (70% as metabolites, <1% unchanged), fecal (20-30%). Codeine: renal (90%, of which 5-10% unchanged, rest as metabolites), fecal (minor).
Category A/B
Category A/B
Antihistamine
Antihistamine / Antiemetic
"The metabolism of Sulfisoxazole can be decreased when combined with Loratadine."