The basis of the results of the survey amounted to 2293 children and adolescents in different regions of Ukraine. It is shown that the prevalence of risky alcohol behavior among children's contingents are significantly higher compared to the drug. Found a significant prevalence of acute intoxication of alcohol on other clinical forms of mental and behavioral disorders due to children's and adolescents psychoactive substances use and determined that the most risky age for poisoning of surfactants are 7 - 15 years. Defined patterns of children's and adolescents alcohol abuse and classified their understanding of psychoactive substances use and determined their transformation with age. Identified and evaluated factors which are promoting acquisition of skills children's psychoactive substances use. Studied the reasons the first attempt and classified biological, personality and psychosocial components of making cause of children's psychoactive substances use. Investigated the clinical phenomenology of mental and behavioral disorders due to children's and adolescents psychoactive substance use: use with risk of adverse effects (39,5%), with adverse effects (22,5%), psychoactive substance addiction (1%). For the first time it was determined the presence of subclinical psychopathological manifestations of hospitalized children with acute psychoactive substances poisoning, namely: anxiety (26,1%), mixed (26,1%), obsessive-phobic (18,4%), asthenic-vegetative (18,4%) and asthenic (10,8%). Biological, psychological and social components of skills formation process children's and adolescents psychoactive substance use were analyzed. It is proved that the biological, psychological and social preconditions of psychoactive substance use are markers of unfavorable prognosis quick development of children's and adolescents psychoactive substance use, and it was determined their corellation in the genesis of the formation of the studied phenomenon. The above-listed preconditions were systematized by the intensity of influence and differentiated as predisposing, promoting and supporting, depending on the way for a first experience of child's psychoactive substance use. The mechanisms shaping the children's and adolescents psychoactive substance use were established: the family personal psychology, psychobiological. Revealed that the presence of additional psychopathological background of psychoactive substance use as a subclinical state of mental desadaptation (maladjustment), increases the intensity of the influence of biological preconditions of children's and adolescents psychoactive substance use skills forming. Based on the generalization of findings, science-based principles and developed a complex multilevel system of prevention and correction of children's and adolescents psychoactive substance use, aimed at forming their self-responsible healthy style position based on their cooperation with parents and teachers, based on learning healthy lifestyle ground on the development of life skills, which consists of informing actions, studying and correction, has differentiated influences, directed to work with children, their parents, school and medical staff, and has the appropriate methodological principles and guidance.
