Dextromethorphan (DXM or DM or DMT) is an antitussive drug. It is one of the active ingredients used to prevent coughs in many over-the-counter cold and cough medicines. Dextromethorphan has also found other uses in medicine, ranging from pain relief to psychological applications. It is sold in syrup, tablet, and lozenge forms manufactured under several different brand names and generic labels. In its pure form, dextromethorphan occurs as a white powder.
When exceeding label-specified maximum dosages, dextromethorphan acts as a dissociative psychedelic drug. Its mechanism of action is as an NMDA receptor antagonist, producing effects similar to those of the controlled substances ketamine and phencyclidine (PCP).
The effects of dextromethorphan abuse vary with the amount taken. Common DXM effects can include confusion, dizziness, double or blurred vision, slurred speech, impaired physical coordination, abdominal pain, nausea and vomiting, rapid heart beat, drowsiness, numbness of fingers and toes, and disorientation. DXM abusers describe different “plateaus” ranging from mild distortions of color and sound to visual hallucinations and “out-of-body,” dissociative, sensations, and loss of motor control.
The abuse of cough medications including DXM can contain other ingredients, such as acetaminophen, which can be very dangerous when taken in large quantities. For example, large quantities of acetaminophen can damage the liver.
DXM is also sometimes abused with other drugs or alcohol, which can increase the dangerous physical effects.