Jasem Clinical Toxicology method introduces a procedure for detecting drugs of abuse such as opioids, amphetamine, methamphetamine, cocaine and metabolites, THC and metabolites, benzodiazepines, antidepressants, atypical antipsychotics, over-the-counter cold medicines as well as routinely used prescription drugs by follow up patients samples by LC/MS-MS. Liquid chromatography tandem mass spectrometry (LC-MS/MS) is analytical technique of choice available for screening and/or quantification of drugs.