[Clinical significance of selective serotonin reuptake inhibitor (SSRI) in the treatment of depression].

SSRIs have had a great impact on the diagnosis and treatment of depression, as well as the search for its pathophysiology. Since SSRIs have relatively few adverse effects, it is also effective for treating in a mild forms of depression, which were formerly thought to be treated adequately with only psychotherapy or anti-anxietics. Recent studies on the natural history of depression have revealed the chronicity of this disease. SSRI is now the first-line drug for the continuation and maintenance therapy of depression. Since SSRI primary acts on the serotonergic system, wide use of this drug has questioned the postulated dichotomy of the biological hypothesis of depression, the so-called serotonin depression or norepinephrine depression. A new insight into the monoamine hypothesis of depression has been yielded by SSRI. SSRIs are also effective in the treatment of anxiety disorders such as obsessive-compulsive disorder, panic disorder and social phobia. Thus, SSRIs have also brought new insight into the role of serotonin in the pathophysiology of anxiety.