The use of non-selective monoamine oxidase inhibitors (IMAO) may be associated with the risk of addiction, which is confirmed by case studies published so far. Harmful use of antidepressants in patients with affective disorders and anxiety is not frequent, but due to the fact that in clinical practice can meet with this phenomenon, we present the case of a 30-year-old patient with a history of using phenelzine who presented a combination of symptoms that meet criteria for addiction. The current classification of ICD-10 does not consist the diagnosis of dependence on antidepressants. In this case, the category F55.0: abuse of a substance which does not cause addiction, should be used. In the literature most often mentioned as a possible substances with addictive potential is a group of non-selective MAO, particularly tranylcypromine. The mechanism of non-selective MAO dependence may be associated with the similarity of their chemical structure to amphetamine (both amphetamine and IMAO are derivatives of phenylethylamine), although the mechanism of action is different. Furthermore, it was noted that there is a group of patients in whom treatment with IMAO is associated with greater risk of abuse of these substances. The study contains the characteristics of this group of patients.