Monophasic refers to cases of simple depressive episodes from the absence of manic episodes, whether they are single episodes or multiple recurrences, regardless of their number. For this reason, a patient, who has had a manic episode in his medical history cannot be considered a monophasic case. Studies have shown that cases with only manic episodes in the form of manic episodes are relatively rare in clinical practice. Monophasic affective disorder: depression, agitation, or anxiety, or a mixture of them, can be seen. In insidious depression, however, the depressive state of mind can conversely be experienced without consciousness. In place of this depressed state of mind, somatic discomfort may occur, even with a smiling face as a defensive mask (smiling depression). Some may complain of various kinds of pain, fear of catastrophe, or fear that they are going crazy. In some cases, the morbid feelings have reached the depth of “no tears” and the ability to cry is restored, indicating improvement. Patients with this type of depression may report an inability to experience ordinary emotions, including sadness, joy, and happiness, and a sense that the world has become a gloomy, dead place. The pathological state of mind may be accompanied by self-blame, self-defeating thoughts, inability to concentrate, indecisiveness, decreased interest in daily activities, social withdrawal, helplessness and disappointment, and recurrent thoughts of death and suicide. In both monophasic and biphasic depressive phases, psychomotor and vegetative nervous system signs are evident. Patients exhibit psychomotor retardation, or slowness of thought, speech, and – in general – movement, which may even progress to depressive miosis, when all voluntary movements disappear completely. About 15% of depressive disorders can have psychotic symptoms, most often seen in melancholic disorders. We hope that you will keep in mind that if you find the disease, you should take prompt action.