Alcohol addiction of methamphetamine abusers in Japan.

Fifty-eight methamphetamine (MAMP) abusers were surveyed to demonstrate the types of nature of MAMP abuse. In-depth interviews using psychophysiological techniques assessed the subjects to be truthful or deceptive about their abuse histories. Research diagnostic criteria determined the subjects clinical symptoms. The results show that three factors characterize MAMP abuse: significant correlation was found between the years of abuse; the manifestation of somatic or mental disorders or both, and alcohol (Alc) addiction. MAMP abusers who were nondrinkers or light drinkers developed a tendency to dislike Alc after MAMP abuse, while there was no change in Alc consumption in heavy drinkers. The findings suggest that the combined abuse of MAMP and Alc aggravates somatic and mental disorders and that Alc plays an important role in the fatal effect of MAMP, especially from small doses. This provides support for the synergistic effects between MAMP and Alc. Coadministration of MAMP and Alc appears to produce long-acting and more complicated changes in the brain's neurotransmitter function.