[Comparison of altered states of consciousness induced by the hallucinogens (--)-delta9-trans-tetrahydrocannabinol (delta9-THC) and N,N-dimethyltryptamine (DMT) (author's transl)].

The study compares altered states of consciousness induced by the hallucinogens (--)delta9-trans-Tetrahydrocannabinol (delta9-THC) and N,N-Dimethyltryptamine (DMT) using two placebo control groups. A total of 24 subjects received 250 mug delta9-THC p.o./kg body weight and 26 subjects were treated with 250 mug DMT i.m./kg. Placebo was given to 24 subjects. The effects were assessed by a questionnaire administered following the experimental conditions. Questionnaire items were combined into the following eight scales according to their content and several cirteria of the theory of mental testing: visual hallucinations (illusions), auditory hallucinations (illusions), impairment of memory and attention, depersonalization syndrome, deprealization syndrome, changes of body image, euphoric state and anxious-depressive state. The two hallucinogen groups differed significantly from placebo on all eight scales. No difference, however, between delta9-THC and DMT was significant. On the scale "optical hallucinations (illusions)" a tendency that DMT might have stronger effects than delta9-THC was found. Methodological problems of comparing different hallucinogens are discussed.