Overview:
Dextromethorphan hydrobromide monohydrate (DM or DXM) is an antitussive drug that is found in many over-the-counter cold and cough preparations. The FDA approved dextromethorphan for over-the-counter sale as a cough suppressant in 1958. This filled the need for a cough suppressant lacking the sedative side-effects, stronger potential for abuse, and physically addictive properties of codeine phosphate, the most widely-used cough medication at the time (now prescription-only in the United States).
During the 1960s and 1970s, DXM became available in an over-the-counter tablet form by the brand name Romilar. It was put on the shelves in hopes of cutting down on codeine cough remedies. In 1973, Romilar was taken off the shelves after a burst in sales due to common recreational use. It was then replaced by cough syrup, in an attempt to cut down on recreational usage.
More recently (around 2000) gel capsule forms began reappearing in the form of Robitussin CoughGels as well as several generic forms of that preparation.
Slang terms for DXM often correlate to the brands of cough medicine used, such as "tussin," "robo," "dex," "triple C's," and "skittles." Recreational use of DXM is frequently referred to in verb form as "dexing," "tussing," "roboing," and "robotripping.
Biochemically, DXM's psychological effects can be attributed largely to dextrorphan (DXO), a chemical by-product (or metabolite) that is produced when DXM metabolizes within the body. Both DXO and DXM are NMDA receptor antagonists, just like the dissociative hallucinogenic drugs ketamine and phencyclidine (PCP).
