Mesocarb (sydnocarb or 3-(beta-phenylisopropyl)-N-phenylcarbamoylsydnonimine) is a psychomotor stimulant N-alkylated amphetamine derivative. Mesocarb is a selective inhibitor of dopamine uptake, it potently blocks dopamine transporter. It is very likely that mesocarb is being used by drug addicts. Mesocarb is included in the World Anti-Doping Agency’s list of substances and methods that are prohibited in sports. It is used in Russia for the treatment of a variety of neuropsychiatric comorbidities.