Adulterants in crack cocaine in Brazil.

Brazil is the world's biggest consumer of crack cocaine, and dependence is a major public health issue. This is the first study to investigate the prevalence of potentially harmful adulterants present in hair samples from Brazilian patients with crack cocaine dependence. We evaluated adulterants in hair samples extracted by convenience from 100 patients admitted at the 48 hour-observation unit of Centro de Referência de Álcool, Tabaco e Outras Drogas (CRATOD), Brazil's largest center for addiction treatment. A cross-sectional analysis was performed with the data obtained. Adulterants were found in 97% of the analyzed hair samples. The most prevalent adulterant was lidocaine (92%), followed by phenacetin (69%) and levamisole (31%). Adulterants were widely prevalent in hair samples from crack users treated at CRATOD: at least one adulterant was present in virtually all the hair samples collected. This points to a need to monitor adverse effects in the clinical setting in order to provide this high-risk group of patients with prompt and effective care related to the acute and chronic complications associated with these adulterants.