Major depressive disorder
Other namesClinical depression, major depression, unipolar depression, unipolar disorder, recurrent depression
SpecialtyPsychiatry
SymptomsLow mood, low self-esteem, loss of interest in normally enjoyable activities, low energy, pain without a clear cause
ComplicationsSelf-harm, suicide
Usual onset20s–30s
Duration> 2 weeks
CausesGenetic, environmental, and psychological factors
Risk factorsFamily history, major life changes, certain medications, chronic health problems, substance abuse
Differential diagnosisBipolar disorder, ADHD, sadness
TreatmentCounseling, antidepressant medication, electroconvulsive therapy, exercise
Frequency216 million (2015)