Paracetamol is a medication that belongs to a class of medications known as analgesics (pain relievers) and antipyretics (fever reducers). Caffeine increases the absorption of paracetamol and enhances its analgesic effect. Phenylephrine hydrochloride is a medication that belongs to a class of medicines known as “decongestants” and acts by decreasing nasal stuffiness that you may experience during cold and flu.