A cough, also called tussis, is the rapid expulsion of air from the lungs in an effort to remove irritants, fluids, microbes, and foreign particles from the respiratory tract. You can cough on purpose or as a reflex. It's true that a persistent cough can be an indicator of anything more serious, but in most cases, it goes away on its own. Recent guidelines have attempted to provide direction in the clinical management of cough in both primary and secondary care.