Antitussives are medicines that suppress coughing, also known as cough suppressants. Antitussives are thought to work by inhibiting a coordinating region for coughing located in the brain stem, disrupting the cough reflex arc; although the exact mechanism of action is unknown.

However, their use is not without controversy and they should only be considered for dry, irritating coughs that do not involve mucus production. Suppressing productive or mucus-producing coughs caused by some respiratory diseases with antitussives may be hazardous. Many viral coughs are best treated by increasing fluid intake and exposing the airways to humidity.

Many antitussives, including pholcodine, codeine, and dextromethorphan, are derived from opioids. Pholcodine and codeine may cause drowsiness and constipation and codeine may be addictive. Dextromethorphan can increase serotonin levels and may interact with other medicines that also increase serotonin. Benzonatate is an nonnarcotic antitussive that anesthetizes certain receptors located in the breathing passages, reducing the urge to cough.

Although antitussives have been shown to be effective in adults, their effectiveness in children has not been established and their use in children should be discouraged.