Antidepressants are used in the treatment of both depressive and anxiety disorders. According to the latest data, the quantity of antidepressants and mood stabilizers used has almost doubled over the last eight years. These numbers are still growing, but the highest increase in the number of patients using this group of drugs was recorded in 2013 (12%) and 2014 (13.1%). The most commonly used group of antidepressants are selective serotonin reuptake inhibitors (SSRIs) (63% of prescribed antidepressants). SSRIs are considered first-choice drugs in the treatment of depressive disorders and chronic anxiety. The number of SSRIs used by patients has more than doubled over the last 8 years. Among selective serotonin reuptake inhibitors, sertraline (38.5% of all prescriptions) was the most commonly used active substance in Poland in 2018. The most frequently prescribed substance belonging to the group of antidepressants with a different mechanism of action was opipramol (23.8% of all prescriptions), followed by trazodone (19.1% of all prescriptions) and mianserin (15.4% of all prescriptions). Out of the two drugs from the group of serotonin and noradrenaline reuptake inhibitors (SNRI) available in Poland, many more patients use venlafaxine (84.2%) than duloxetine (15.8%). A similar trend related to a constantly growing number of antidepressants used is also observed in other European countries and in the United States of America.