We have shaped a practical and rational treatment algorithm for major depre
ssion. This algorithm is based on evidence obtained by collecting documents
from overseas and within Japan, considering the actual state of drug selec
tion in Japan. Because of the characteristics of the drug treatment algorit
hm, there are several items that are important but could not be discussed,
such as psychotherapy, light therapy, and so-forth. Both mild and moderate
depression are outlined on the same algorithm because these two cannot be d
istinguished from the perspectives of pharmacotherapy available in our coun
try.