Mequinone is a hypnotic sedative. It is sold under brands such as Quaalude (/ KOMp w e Be u Sample d/KWAY-lood) and Sopor, which contains 300 mg of methaqualone, and under the brand name Mandrax as a combination drug, It contains 250 milligrams of mequinone and 25 milligrams of diphenhydramine in the same pill, mostly in Europe. Commercial production of mequinone was discontinued in the mid-1980s due to widespread abuse and addiction. It is a member class of quinazolinone.

The sedative and hypnotic effects of mequinone were first discovered in 1955. In 1962, Wallace and Tiernan obtained a U.S. patent for mequinone. Its use peaked in the early 1970s as a treatment for insomnia and as a sedative and muscle relaxant.

Mequinone grew in popularity as a recreational drug and club drug in the late 1960s and 1970s, and was referred to as “ludes” or “disco cookies” [citation needed] due to its widespread use during the 1970s disco craze, Or “sopers” (also called “soaps”) in the United States and Canada, and “mandrakes” and “mandies” in the United Kingdom, Australia, and New Zealand. The substance is sold in the form of free bases and salts (hydrochloride). This use means that the drug is controlled in most countries/territories and therefore falls under the United Nations Convention on Psychotropic Substances