Cough syrup Dextromethorphan is a drug used in many over-the-counter cough and cold medicines for its antitussive effects. It comes in oral strips, lozenges, liquids, or liquid-filled capsules and formulations often combine the drug with guaifenesin, acetaminophen, and pseudoephedrine. Dextromethorphan is also a commonly abused drug because of its euphoric, hallucinogenic, and dissociative properties. This activity reviews the presentation, evaluation, and management of dextromethorphan toxicity