High pressure liquid chromatographic determination of antihistamine-adrenergic combination products.

Reverse phase high pressure liquid chromatography (HPLC) with ion-pairing is used for the determination of pseudoephedrine hydrochloride in combination with triprolidine hydrochloride or chlorpheniramine maleate in sirups and tablets. Sirups require a preliminary column chromatography cleanup step. Response is linear for pseudoephedrine hydrochloride (range of 0--20 micrograms), chlorpheniramine maleate (range of 0--1.3 micrograms), and triprolidine hydrochloride (range of 0--1.0 micrograms). Recoveries from synthetic formulations were 98.8--101.3% for pseudoephedrine hydrochloride, 100.0--101-2% for chlorpheniramine maleate, and 97.7--99.8% for triprolidine hydrochloride. The coefficient of variation for the method is less than 1%.