In drug users' jargon, an adverse effect of drug use, consisting of any mixture of the following: feelings of losing control, distortions of body image, bizarre and frightening hallucinations, fears of insanity or death, despair, suicidal thoughts, and strong negative affect. Physical symptoms may include sweating, palpitations, nausea, and paraesthesia. Although adverse reactions of this type are usually associated with the use of hallucinogens, they may also be caused by the use of amphetamines and other psychomotor stimulants, anticholinergic, antihistamines, and sedatives/hypnotics.
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