Mechanisms and abuse liability of the anti-histamine dimenhydrinate

Abstract

The over-the-counter anti-emetic dimenhydrinate (DMH) (Gravol or Dramamine) has been reported to be abused for non-medicinal purposes. Street drug users abuse DMH for the acute effects of euphoric sensations and hallucinations, while psychiatric patients abuse DMH for its anxiolytic or anti-cholinergic effects. DMH is an H 1 histamine receptor antagonist, but it interacts either directly or indirectly with other neurotransimitter systems, including those using acetylcholine, serotonin, norepinephrine, dopamine, opioids or adenosine. Animal behavioural studies, such as self-administration, conditioned place preference, drug discrimination, and modulation of operant responding, show that anti-histamines have abuse potential. Further support comes from reports of acute and chronic abuse of DMH by humans. Collectively, results confirm the abuse liability of DMH.