Skip to Main Content

We have a new app!

Take the Access library with you wherever you go—easy access to books, videos, images, podcasts, personalized features, and more.

Download the Access App here: iOS and Android. Learn more here!

For further information, see CMDT Part 25-12: Mood Disorders (Depression & Mania)

Key Features

Essentials of Diagnosis

  • In most depressions

    • Mood varies from mild sadness to intense guilt, worthlessness, and hopelessness

    • Difficulty in thinking and concentration, with rumination and indecision

    • Loss of interest, with diminished involvement in activities

    • Somatic complaints

    • Disrupted, reduced, or excessive sleep

    • Loss of energy, appetite, and sex drive

  • In some severe depressions

    • Psychomotor disturbance: retardation or agitation

    • Delusions of a somatic or persecutory nature

    • Withdrawal from activities

    • Suicidal ideation

General Considerations

  • Sadness and grief are normal responses to loss; depression is not

  • Unlike grief, depression is marked by a disturbance of self-esteem, with a sense of guilt and worthlessness

  • Persistent depressive disorder (dysthymia) is a chronic depressive disturbance with symptoms generally milder than in a major depressive episode


  • Up to 30% of primary care patients have depressive symptoms

  • The COVID-19 pandemic has undoubtably increased the risk of depression

  • One meta-analysis of studies of community-based prevalance of depression found a seven-fold increase in depression in some heavily impacted communities in Europe and Asia

  • US national surveys show a three-fold increase in the prevalence of depressive symptoms, with risk factors including lower income, < $5000 in savings, and exposure to stressors

Clinical Findings

Symptoms and Signs

  • Anhedonia

  • Withdrawal from activities

  • Feelings of guilt

  • Poor concentration and cognitive dysfunction

  • Anxiety

  • Chronic fatigue and somatic complaints

  • Diurnal variation with improvement as the day progresses

  • Vegetative signs

    • Insomnia

    • Anorexia

    • Constipation

  • Occasionally, severe agitation and psychotic ideation

  • Atypical features

    • Hypersomnia

    • Overeating

    • Lethargy

    • Mood reactivity

Differential Diagnosis

  • Bipolar disorder or cyclothymia

  • Adjustment disorder with depressed mood

  • Dysthymia

  • Premenstrual dysphoric disorder

  • Major depression with postpartum onset: usually 2 weeks to 6 months postpartum

  • Seasonal affective disorder

    • Carbohydrate craving

    • Lethargy

    • Hyperphagia

    • Hypersomnia


Laboratory Tests

  • Complete blood count

  • Serum thyroid-stimulating hormone

  • Serum folate

  • Toxicology screen may be indicated

  • Blood tests to diagnose depression and predict antidepressant response are being developed



  • See Table 25–7 and Figure 25–2

  • Selective serotonin reuptake inhibitors (SSRIs) and atypical antidepressants

    • Generally lack anticholinergic or cardiovascular side effects

    • Most are activating and should be given in the morning

    • Some patients may experience sedation with paroxetine, fluvoxamine, and mirtazapine

    • Clinical response varies from 2 to 6 weeks

    • Common side effects are headache, nausea, tinnitus, insomnia, nervousness

    • Sexual side effects (eg, erectile dysfunction) are very common and may respond to sildenafil

    • "Serotonin syndrome" may occur when SSRIs are taken in conjunction with monoamine oxidase inhibitors or selegiline

    • With the exception of paroxetine, SSRIs should be tapered over weeks to months to avoid ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.