The analysis of drugs in saliva is a non-invasive alternative to demonstrate their presence in the body. The purpose is broad, but it has been used in forensic and legal medicine, especially for illicit drugs. The collection of saliva is not risky and does not require specialized personnel. The objective was to assess various methodological and validity aspects of the saliva drug test for the diagnosis of drug use. Likewise, some aspects related to drug legislation were analyzed. The psychoactive substances to be evaluated were marijuana, cocaine, amphetamines and opiates. A search was carried out in the Pubmed / MEDLINE, Embase, LILACS, Scopus, SciELO and gray literature databases. Identification of drugs in biological fluids was found to include immunochemical, chromatographic and spectrometric procedures. Positive results obtained by one technique must be confirmed with a second analy...