INTRODUCTION: Suicide is a complex interdisciplinary subject engaging different aspects of human functioning. One of the approaches is the phenomenological understanding of suicide which considers suicidal impulses as a result of individuals' suffering, not necessarily indicated with specific psychiatric disorders. At the same time there is evidence that suicide is associated with brain chemistry disturbances as oxidative stress. OBJECTIVE: The objective of this study is to determine if oxidative stress components are related to suicide ideations.METHOD: The study included subjects aged 18u201364 (N=48) recruited at the Clinic of Psychiatry, Faculty of Health Sciences, Medical University of Warsaw, Poland. The participants of the study had different psychiatric diagnosis. Blood specimens were collected from subjects and measured for oxidative stress biomarkers: nitric oxide metabolites (NOx) and advanced oxidation protein products (AOPP). Subjects were divided in two groups: with (N=31) and without (N=17) suicide ideations in the last three months and compared by the Mann-Whitney U test, Kolmogorov-Smirnov two sample test and Wald-Wolfowitz runs test. Moreover the Spearman's rho correlations between oxidative stress components (NOx and AOPP) and the intensity of suicide ideations in the last month were assessed. The researchers used Columbia Severity Suicide Scale for suicidality assessment. RESULTS: Subjects with a history of suicide ideations in the last three months had significantly higher levels of NOx and AOPP. Furthermore the levels of NOx and AOPP were both positively correlated to suicidal thoughts intensity. CONCLUSIONS: The study revealed that phenomenological aspect of suicide as suicidal ideations is consistent with oxidative stress components levels (NOx and AOPP) which play a significant role in the pathophysiology of suicide.