Pholcodine is a drug which is an opioid cough suppressant (antitussive). It helps suppress unproductive coughs and also has a mild sedative effect, but has little or no analgesic effects. It is also known as morpholinylethylmorphine. Pholcodine is readily absorbed from the gastrointestinal tract and freely crosses the blood–brain barrier. It acts primarily on the central nervous system (CNS), causing depression of the cough reflex, partly by a direct effect on the cough centre in the medulla. It is metabolized in the liver and its action may be prolonged in individuals with hepatic insufficiency. Pholcodine is slowly biotransformed in the body via oxidation and conjugation to a series of metabolites that are eliminated primarily in the urine. With an average half-life of approximately 2.3 days, steady-state in someone taking the drug chronically would not be reached for nearly 2 weeks.