Brief Answer:
this is an old term in psychiatric literature

Detailed Answer:
Hello

This endogenous depression is an old terminology.
Endogenous depression is primarily biological and genetic in nature and exogenous/reactive depression is in reaction to stressful life events

For individuals with endogenous depression, symptoms often appear “out of nowhere” and for no apparent reason.

Although stressful events often precipitate both types of depression, people with the endogenous form are more likely to relapse than those whose depression is more reactive in nature.

Hope this answers your query.

Feel free to ask further.

Kindly close the discussion if you are satisfied with the response and give your valuable feedback.

Thanks.
Dr. Shubham Mehta, MD.

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