The World Health Organization raises self-care as a strategy for health promotion. Although self-medication is included in self-care strategy, often it is associate to an irrational medicine's usage. This factor associated with illicit drugs and alcohol consumption becomes in a public health problem. In order to establish frequency of self-medication and the prevalence of illicit drugs and alcohol consumption among university students of La Plata, Argentina, was started the present project. Information was collected by anonymous survey, that evaluated age, sex, origin, cohabitants, type, frequency of consumption, and career. A total of 5170 students were polled. 46.64 % consumes regularly some medicine and 50.11 % of this consumption was self-medication. Mainly this consumption consisted in analgesics (88 %) and antibiotics (45 %). Benzodiazepines were also consumed in 6.9 % (39 % by self-medication). The consumption of illicit drugs was 38.1 % (29 % marihuana, 4 % cocaine, 1,2 % "paco" and 2.9 % "ecstasy"). The consumption of alcoholic drinks was 82 % for beer, 56 % fernet, 55 % wine and 48 % whiskey. Medicines were obtained outside pharmacies in 30.1 % of the cases. The major consumption of cocaine was given among students of Social Careers [Odds Ratio (OR) 2.3], and in those that lives without their families (1.5). The results indicate that self-medication is common among university students. Those students that live alone had a significant higher risk of being self-medicated than those that lives with their families. More than 30 % of the medicines were obtained at the informal market (other place that pharmacies).