Chiral Switches of Tramadol Hydrochloride, a Potential Psychedelic Drug-Past and Future.

The chiral opioid analgesic tramadol was patented (1962) as a - and -racemates mixture. A first chiral switch led to the (±)--(1,2) racemate, patented and approved as Tramal (1980), preferred over the (+)--(1,2)-enantiomer. Consecutive chiral switches of (±)--tramadol to (+)--(1,2)-tramadol/salts were patented. This Viewpoint calls for developing (+)--(1,2)-tramadol medicines and recognizing tramadol medicines as potential psychedelics to overcome the spreading tramadol crisis.