[Recent neurobiological data on cannabis]

The alarming increase in cannabis abuse has triggered a renewed interest in the neurobiological mechanisms which underlie its effects, particularly as regards its addictive properties either intrinsic or when crossed with other narcotics as well as its subsequent damage. We here report an evaluation of experimental data which reveal in animals a psychological dependence, common to all addictive drugs; a physical dependence, which is considered up to now as the characteristic of "hard addictive drugs"; the incentive effect that cannabis should exert on the inclination to abuse other addictive drugs, especially heroin; and finally the close relationships which seem to exist between cannabis and schizophrenia. Most of these recent data are far from reassuring as regards cannabis psychotoxicity. Furthermore they underline its potential danger and prompt increased caution.