amyl nitrite, drug once commonly used in the treatment of angina pectoris, a condition characterized by chest pain precipitated by oxygen deficiency in the heart muscle. Amyl nitrite is one of the oldest vasodilators (i.e., agents that expand blood vessels). The drug is useful in treating cyanide poisoning. Amyl nitrite, a clear, pale yellow liquid with a penetrating odour, is administered by inhalation and is very rapidly absorbed from the lungs. Its action is nonspecific; i.e., it affects all smooth muscles, causing them to relax. Side effects include headache, increased heart rate (tachycardia), and low blood pressure (hypotension).
Amyl nitrite is often used illicitly to produce euphoria and to enhance sexual pleasure. On the black market the drug is known by a variety of other names, including “amy” and “poppers.” Abuse of the drug can cause severe toxicity.