From year to year, dependence of opiates is a big problem in society. The number of addicted patients is rapidly growing, also the number of deadly issues of overdose is in growing tendency. Most of the researches showed that among addicted to opiates, are number of people with mental disorders, fragile health, criminal past and unemployed. Methadone substitution treatment is an effective treatment which is harm reduce and is maintaining abstinence from opiates.

The sample consisted of 50 patients on methadone substitution therapy in the Methadone center, Sombor. Subjects were tested with inventories which explore trait and state depression and anxiety, and trait of psychopathic deviation.

The objectives of the research were:

1. (1) To collect socio-demographic data of patients on methadone substitution therapy.

2. (2) To make a pilot study by which the predictors of becoming addicted can be identified, based on instruments that measure anxiety, depression and psychopathic deviation

The instruments: trait anxiety, state anxiety, state depression, trait depression, psychopathic deviation, POMPIDOU.

The results confirmed the hypothesis that there is a connection between the first and the regular use of psychoactive substances (PAS). Psychopathic deviation proved to be a significant predictor of becoming dependent - the higher the score on psychopathic deviation scale was, the earlier the patient had become addicted. Hierarchical regression analysis found that PAQ (psychopathic deviation) score explains 18% of the variance of the dependent variable (regular use of PAS). Later borns had significantly higher scores on trait and state depression, compared to the first born.