In recent years, along with the expansion of medical care for depressive disorder, there has been much controversy regarding the application of antidepressant drugs for its treatment. The aim of this paper is to consider critical issues concerning the threshold of application of antidepressant drugs for the treatment of depression. It was formerly important to diagnose the 'quality' of depression (melancholia or non-melancholia) in order to choose antidepressant treatment, whereas an assessment of the 'quantity' of depression (severity of symptoms) is crucial today to decide on the threshold. Recent guidelines for the treatment of major depressive disorder do not positively recommend the use of medication for the treatment of mild depression. The guidelines published by the Japanese Society of Mood Disorders also state that doctors have to give priority to treatments avoiding medication, although the effectiveness of antidepressant drugs for mild depression is controversial. Actually, in a clinical setting, doctors have to understand the conditions of individual cases and cope with many issues, such as a risk of suicide, comorbidity of other psychiatric disorders, target symptoms of pharmacotherapy, and choices of classes and doses of antidepressant drugs. The threshold of application of antidepressant drugs for the treatment of depression may vary according to the doctor-patient relationship and surrounding conditions. Doctors are required to provide treatment options other than pharmacotherapy.
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