Quantitation of acetaminophen, chlorpheniramine maleate, dextromethorphan hydrobromide, and phenylpropanolamine hydrochloride in combination using high-performance liquid chromatography. 
A high-performance liquid chromatographic (HPLC) method has been developed for the quantitation of acetaminophen, chlorpheniramine maleate, dextromethorphan hydrobromide, and phenylpropanolamine hydrochloride in combination in pharmaceutical dosage forms using a single column and three different mobile phases.  The method developed is sensitive for the content uniformity test for tablets.  No preliminary extraction procedure is required for liquid preparation and a very simple extraction procedure is required for tablets.  The method is accurate and precise with RSD (based on five injections) of 1.2, 2.4, 1.9, and 1.6% for acetaminophen, chlorpheniramine, dextromethorphan, and phenylpropanolamine, respectively.