HPLC Separation of NyQuil Active Ingredients

NyQuil is a cough medication produced by Procter&Gamble. It consists of acetaminophen, pseudoephedrine, doxylamine and dextromethorphan. Most of the analytical HPLC methods include either use of ion-pairing reagent or a gradient elution. Mixed-mode chromatography allows to replace long gradient method with short isocratic method. All four compounds are well separated within 3-5 minutes. Methods can be optimized for analysis of other cough composition containing general cough suppressants and pain killers. Method is robust and being validated at several drug companies.


Column Primesep C, 4.6x50 mm, 5 µm, 100A
Mobile Phase MeCN
Buffer TEAPh
Flow Rate 1.0 ml/min
Detection UV, 210 nm


Class of Compounds Drug, Analgetic, Acid, Hydrophilic, Ionizable,
Analyzing Compounds Acetaminophen, Pseudoephedrine, Doxylamine, Dextromethorphan

Application Analytes:
Acetaminophen (Paracetamol)
Pseudoephedrine (PSE)