Current and future peripherally-acting antitussives.

Cough is among the most common complaints for which medical evaluation is sought. The clinical significance of this problem is evidenced by the enormous financial expenditure on prescription and non-prescription cough remedies worldwide. Centrally-acting antitussive agents, such as opiates, are often associated with undesirable or intolerable side effects, including sedation, nausea, and constipation. Therefore, safe and effective peripherally-acting antitussive agents are particularly desirable. Relatively few commercially-available products suppress cough through a peripheral mechanism of action. Recent research in the field of cough has resulted in the development of several new classes of compounds that may prove to be clinically useful peripherally-acting antitussives.