Methaqualone became increasingly popular as a recreational drug in the late 1960s and early 1970s, known as Quaaludes, or 'ludes.
Methaqualone (Quaalude) is a sedative-hypnotic drug that is similar in effect to barbiturates, a general central nervous system depressant. The sedative-hypnotic activity was first noted by Indian researchers in the 1950s and in 1962 methaqualone itself was patented in the US by Wallace and Tiernan. The drug was sometimes used during sexual activity due to heightened sensitivity and lowered inhibition coupled with relaxation and euphoria.
Methaqualone was manufactured in the United States under the name Quaalude by the pharmaceutical firms Rorer and "Lemmon" with the numbers 714 stamped on the tablet, so people often referred to Quaalude as 714s, "Lemmons", or "Lemmon 7s".