What is depression?

Depression is a common, treatable medical condition characterized by persistent low mood, loss of interest or pleasure, and changes in sleep, appetite and concentration. Clinicians describe it as more than normal sadness; it can impair daily functioning and increase risk of self-harm.

According to diagnostic guidelines such as the DSM-5, major depressive disorder involves symptoms present most of the day, nearly every day, for at least two weeks. Symptoms can include persistent sadness, decreased energy, difficulty concentrating, changes in weight or appetite, insomnia or hypersomnia, feelings of worthlessness, and recurrent thoughts of death.

Researchers and clinicians point to a mix of biological, psychological and social contributors. Genetic predisposition, altered neurotransmitter function, chronic medical illness, stressful life events and social isolation are commonly cited risk factors. Dr. Jane Smith, a board-certified psychiatrist at University Medical Center with 15 years treating mood disorders, explained, “Depression is multifactorial; effective care addresses both symptoms and underlying drivers.”

Evidence-based treatments include psychotherapy—such as cognitive behavioral therapy—antidepressant medications, and combinations of both. For severe, treatment-resistant cases, options may include electroconvulsive therapy or newer interventions delivered by specialists. Lifestyle measures like regular physical activity, sleep regulation and social support can augment clinical care.

Public health authorities note depression is a leading cause of disability and contributes substantially to health burden. Early recognition and prompt, evidence-based treatment improve outcomes. Anyone experiencing suicidal thoughts or unable to care for themselves should seek immediate help by contacting emergency services or a crisis support line. Health professionals encourage ongoing follow-up, destigmatization of mental health care and accessible services to reduce suffering.

Primary care commonly uses the PHQ-9 screening questionnaire to detect depression and guide referral. Telehealth and integrated behavioral-health programs have broadened access, but socioeconomic disparities, limited provider availability and stigma still hinder timely treatment for many patients across the population.