Depression has since long remained an up-to-date and inexhaustible topic. A steady increase is still observable in the number of scientific studies exploring various facets of clinical manifestations, aetiology, mechanisms and determinants of depression. This paper elaborates on a particular type of depression – seasonal affective disorder (SAD). This condition usually lasts from a few weeks to a few months and occurs most often in the third decade of life, seldom in children. The diagnosis is from 2 to 3 times more frequent in women. After diagnosis and launching treatment, the symptoms can persist from 2 to 11 years. Some people fully recover from the disorder, or present only mild symptoms. As many as approximately 33% to 44% of patients, develop the major depression episode. In the world statistics the seasonal depression, apart from allergies and AIDS, is placed on the 4th position in the most common health issues. Even up to 10% of people in Poland, feels that the shortening of the day is linked to their general well-being and displays more or less severe symptoms of this condition. This study is a review of the latest literature on the pattern of the seasonal affective disorder. The aetiology of SAD, its psychopathological manifestations and differential diagnosis criteria will be discussed. Practical implications will also be suggested with regard to coping with the symptoms, possibilities of preventing relapses and specificity of the professional counseling for people suffering from SAD.

seasonal affective disorder, depression, affective disorder, aetiology, diagnosis, therapy