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Unipolar treatment resistant depression in adults: Epidemiology, risk factors, assessment, and prognosis

Michael Thase, MD
K Ryan Connolly, MD, MS
Section Editor
Peter P Roy-Byrne, MD
Deputy Editor
David Solomon, MD


Many patients presenting with unipolar major depression (major depressive disorder) do not recover after their initial treatment. As an example, one prospective observational study found that among 3671 outpatients who were treated with citalopram, remission occurred in 37 percent [1]. In addition, patients who fail their initial treatment often do not respond to subsequent trials, and frequently experience a course of illness marked by chronic depression, impaired psychosocial functioning, and poor overall general health [2].

This topic reviews the epidemiology, risk factors, assessment, identification, and prognosis of treatment resistant depression. The treatment of resistant depression and highly resistant (refractory) depression are each discussed separately, as are the initial treatment of depression and the clinical features and diagnosis of depression.

(See "Unipolar depression in adults: Treatment of resistant depression".)

(See "Unipolar depression in adults: Management of highly resistant (refractory) depression".)

(See "Unipolar major depression in adults: Choosing initial treatment".)  


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Literature review current through: May 2017. | This topic last updated: Mar 08, 2017.
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