Tianeptine, an unapproved drug known as "gas station heroin," is sold in the U.S. as a nootropic despite not being cleared by the FDA for medical use.

Tianeptine, an unapproved drug known as "gas station heroin," is sold in the U.S. as a nootropic despite not being cleared by the FDA for medical use. Launched in Europe in the 1980s, it is not on the list of federally controlled substances, yet experts warn it is dangerous due to potential for dependency and overdose risks. Tianeptine targets the mu opioid receptor like other opioids, which has led to its abuse and addiction. Its exact mechanism of action remains unknown, but research shows it can cause respiratory depression and severe sedation.