Metamphetamin-bedingte psychische Störungen

Methamphetamine is one of the world's most famous stimulants and was synthesised for the first time in the thirties of the last century. During the 20th century it was first used as a combatant drug in a military context,then as classical doping compound in sporting competitions and last but not least, as recreational drug called "speed" in a hippie-subculture. These days, it is widely spread as an ingredient of the so-called "Thai-Pill". The objectives of this article are: a) a brief presentation of the history of this stimulant, b) a concise description of the clinical effects, side effects and characteristic complications, c) giving an overview of the state of art as to the therapeutical means in treating methamphetamine-related mental and physical disorders. The molecular mechanism of the psychoactive methamphetamine effect consists in a dopamine-liberation as well as a reuptake inhibition at the presynaptic neuronal membrane. Analogous effects also take place on noradrenergic neurons. Subsequently, the author elucidates the symptomatology and pathogeny of the methamphetamine-psychosis, a clinical syndrome displaying at least six distinct subtypes. Models of the underlying neuronal processes are largely based upon animal experiments. The crucial phenomenon seems to be the "lasting behavioural sensitisation" of the dopaminergic system, which induces two distinct forms of stereotype motor behaviour, of which one can be dissociated by a noisy stimulus and one which can not. The second type, which is especially apt to model psychotic behaviour, can only be elicited by potent stimulants like methamphetamine and cocaine. As to the treatment it is obvious that in the case of methamphetamine-related disorders, one has often to cope with a somatic and a psychiatric emergency situation at the same time. Complications can either result directly from the intoxication or indirectly from the disinhibited behaviour. Agitation and psychotic symptoms respond comparably well to benzodiazepines and neuroleptics in which the atypical ones are to be preferred because of their higher efficiency and lower side effect profile. Finally, the conclusion is drawn that in view of this growing problem it is certainly worthwhile for mid-European psychiatrists to get acquainted with the state of the art in making the diagnosis and providing adequate treatment for these partly life-threatening states.