Depression

Depression is a mood disorder involving persistent sadness, loss of interest or pleasure and related changes in sleep, appetite, energy and concentration that last for weeks or longer.

Major depressive disorder is diagnosed when symptoms persist most of the day, nearly every day, for at least two weeks and impair functioning; other forms include persistent depressive disorder, seasonal patterns and depression linked to childbirth. Feelings of worthlessness, slowed movement, unexplained aches and thoughts of death or suicide can also occur. Genetics, life stress, medical illness and certain medications contribute to risk.

Clinicians assess depression through interview and standardized questionnaires such as the PHQ-9, ruling out thyroid disease and other medical mimics. Psychotherapy, antidepressant medication and, for severe cases, brain stimulation therapies are established treatments. Human evidence specific to cannabidiol in depression is limited, with most findings coming from animal models or secondary outcomes in trials designed for other conditions.