In this book the author wants to discuss from the clinical and biochemical points of view some aspects of the dynamics of anxious depression under the treatment with serotonergic antidepressants with different mechanisms of action on serotonin reuptake - inhibitor and enhancer. The underlining biochemical and hormonal changes are described. There were investigated the conformational changes of the albumin molecule in patients with anxious depression in dynamics of pharmacotherapy with antidepressant - tianeptine using subnanosecond fluorescence laser spectroscopy with specific fluorescent probe CAPIDAN. There was performed comparative analysis of the conformational changes in patients with anxious and melancholic depression. In anxious depression all amplitudes before treatment were significantly lower than in healthy controls whereas in melancholic depression before the treatment amplitudes were higher as compared with controls. These results point out that that the two types of depression - anxious and melancholic - have different metabolic profile.