Inroduction: Oxidative stress is an important pathogenetic factor in a number of socially significant diseases, including the acute exogenous poisoning. Homocysteine is a sulfur-containing amino acid synthesized on the basis of methionine, which plays an important role as an oxidizing agent in the human body. As such a factor, it was the monitored subject of this study.

Aim: To measure the level of homocysteine in acute exogenous poisoning with alcohol, heroin and cerebro-toxic drugs.

Materials and methods: This is a prospective longitudinal study including 118 patients with moderate or severe acute poisoning with cerebro-toxic drugs (n=45), alcohol (n=40), heroin (n=33) and a “control group” (n=35). Clinical laboratory tests were performed according to the standards of a clinical laboratory. In the statistical analysis we used alternative and variance analysis, parametric methods for hypothesis assessment, and nonparametric methods for normal distribution.

Results and discussion: The results showed that for the three groups of intoxications, the average homocysteine levels were higher than those of the control group (р<0.001). The intergroup comparison criterion for normal distribution showed that the changes in patients with alcohol intoxication (u=3.39; р<0.001) and heroin intoxication (u=2.00; р<0.001) were highly statistically significant without correlating with the severity of the poisoning (р>0.05).

Conclusion: There is a risk of oxidative stress in intoxication with alcohol and narcotics. A reliable marker for the complex evaluation of oxidative stress in people is monitoring the serum level of homocysteine and its careful interpretation.