To study clinical efficacy of the main representatives of SSRI (citalopram, paroxetine, sertraline, fluoxetine, fluvoxamine) in treatment of depressive episode, recurrent depressive disorder, bipolar depression moderate and severe degree. To reveal features of clinical dynamics during therapy above mentioned medicines and to establish optimal dosing regimen depending on type and severity degree of depression.

Examined 3 groups of patients treated with SSRI: 131 with a depressive episode, 194 with recurrent depressive disorder, 230 with bipolar affective disorder. During the research analyzed following indicators: severity of general therapeutic effect (number of responders on a scale general clinical impressions of effectiveness of therapy); degree of reduction of depression’s symptoms on scale Hamilton depression; timing of positive therapeutic effect; general frequency and severity of side effects, the most frequently reported side effects (on a scale of evaluation of side effects).

When evaluating effectiveness of SSRI treatment revealed a number of clinico-pharmacological patterns. In the group with BD is determined statistically significant a slower decrease in level of depression with correlation relationship between dynamics of improvement of depressive affect and degree of cognitive impairments. Maximum side effects in all groups was observed during first three weeks of treatment.

Determined factors of choice for treatment with each of above mentioned SSRI and optimal dosage regimen; estimated range of timoanaleptical activity in relation to different as typological structure, and degree of severity of depression in various age groups of patients; described features of timoanaleptical action on different quantitative and qualitative components of depressive episode.