Methaqualone, introduced in the 1960s as a sedative-hypnotic alternative to barbiturates, was withdrawn from the market due to its side effects and growing recreational use. Despite this, interest in methaqualone and its analogs remains high, raising concerns about potential abuse in the future. An ultra-high-performance liquid chromatography method coupled with triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS) was developed to determine nine methaqualone-related compounds simultaneously. Biological samples were prepared using liquid-liquid extraction with ethyl acetate at pH9
quantification was performed in blood using multiple reaction monitoring (MRM) mode. Methaqualone-