GP · mental-health
Depression in adults
Also known as Major depressive disorder · Major depressive episode · Clinical depression · Unipolar depression
GP-fellowship guide to depression in adults: the DSM-5 criteria and PHQ-9 severity bands that structure diagnosis, the differential that must be cleared before prescribing (bipolarity, bereavement, hypothyroidism, anaemia, substances), suicide risk assessment and safety planning, stepped care from watchful waiting to CBT, IPT and SSRIs, the landmark evidence (PHQ-9 validation, STAR*D remission rates, Cipriani's 21-antidepressant network meta-analysis, lithium augmentation, ECT), continuation and maintenance durations, and the special populations — perinatal and older adults — where prescribing judgement matters most.
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Red flags
- Screen for bipolarity before every antidepressant script — a positive Mood Disorder Questionnaire (7 or more items) or any past elevated mood while on an antidepressant means mood-disorder review, not another SSRI
- Any expression of suicidal intent, plan or a suicide attempt requires same-consultation structured risk assessment, means restriction and documented safety planning — never close the consultation on reassurance alone
- Severe depression with psychotic features, refusal of food and fluids, or imminent high risk is an emergency psychiatric referral and an ECT discussion, not a routine trial of oral antidepressants
- Activation, insomnia and rising energy within the first 2 weeks of an SSRI demand review for emerging hypomania — the classic missed diagnosis is bipolar depression treated with an antidepressant alone
Overview
Major depressive disorder is among the most burdensome health conditions worldwide. Between 1990 and 2019, the global burden of mental disorders rose from 80.8 million to 125.3 million DALYs, mental disorders moved into the top ten leading causes of global burden, and years lived with disability contributed almost all of it — depressive disorders are the largest single contributor.[30] In Australia, 17.4% of adults aged 16–85 consulted a health professional for their mental health in 2020–2022, up from 11.9% in 2007; general practitioners recorded a 53% increase in their share of that work.[31] Depression is therefore core general practice business, and most treated depression is managed wholly in primary care.
Depression is also a highly recurrent condition. Recurrent depression reflects an underlying vulnerability that is largely genetic in nature, and each episode increases the risk of the next.[22] The consulting-room consequences follow directly: treat episodes to full remission, continue treatment long enough, and take recurrence history seriously when planning duration.
References36ShowHide
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