Depression

Key Points

• Depression is a group of mood disorders characterized by a persistently depressed or irritable mood, loss of interest/pleasure (anhedonia), and associated cognitive and physical symptoms that impair functioning.
• Major Depressive Disorder (MDD): ≥5 of 9 DSM-5-TR criteria present for ≥2 weeks; at least one symptom is depressed mood OR anhedonia.
• Types: MDD, persistent depressive disorder (dysthymia), premenstrual dysphoric disorder (PMDD), postpartum depression, and seasonal affective disorder.
• Treatment: 80–90% of people with depression respond well to treatment — antidepressants, psychotherapy, ECT, TMS, and self-care.
• Priority assessment: suicide risk screening (PHQ-9, Columbia Suicide Severity Rating Scale); immediate provider notification for suicidal ideation with plan.
• Antidepressants: SSRIs are first-line; monitor for serotonin syndrome; MAOIs require tyramine dietary restrictions.
• In serious illness contexts, persistent hopelessness/helplessness or suicidality is not considered normal grief and requires urgent escalation.

Pathophysiology

Depression involves dysregulation of neurotransmitters — particularly serotonin, norepinephrine, and dopamine — within the brain’s limbic system and prefrontal cortex. Neuroimaging studies show decreased activity in the prefrontal cortex and hippocampal volume loss in chronic depression.

Risk factors: personal or family history of depression, trauma, chronic illness, substance use, hormonal changes, and social isolation.

Types of Depressive Disorders

Type	Duration	Key Features
Major Depressive Disorder (MDD)	≥2 weeks	5+ DSM-5-TR criteria; one must be depressed mood or anhedonia
Persistent Depressive Disorder (Dysthymia)	≥2 years	Chronically depressed mood; less severe but persistent
Postpartum Depression	Within 1 year of childbirth	Depressive episode triggered by hormonal changes postpartum; severe untreated episodes can progress to postpartum psychosis emergency
Premenstrual Dysphoric Disorder (PMDD)	Recurrent; luteal phase	Severe mood changes, irritability, and depression in week before menses
Seasonal Affective Disorder (SAD)	Seasonal pattern	Depression onset in fall/winter; responds to light therapy

DSM-5-TR Criteria for Major Depressive Disorder

Diagnosis requires 5 or more of the following 9 symptoms during the same 2-week period — at least one must be (1) depressed mood OR (2) anhedonia:

1. Depressed mood most of the day, nearly every day
2. Anhedonia — markedly diminished interest or pleasure in activities
3. Significant weight loss or gain (>5% body weight in a month) OR decreased/increased appetite
4. Insomnia or hypersomnia nearly every day
5. Psychomotor agitation or retardation (observable by others)
6. Fatigue or loss of energy nearly every day
7. Feelings of worthlessness or excessive guilt (not merely self-reproach)
8. Diminished ability to think or concentrate; indecisiveness
9. Recurrent thoughts of death, suicidal ideation without a specific plan, or a suicide attempt

Suicidal Ideation — Immediate Action Required

Recurrent thoughts of death or suicidal ideation (item 9) requires immediate assessment of suicide risk. Active suicidal ideation with plan → notify provider immediately, initiate safety precautions.

Nursing Assessment

Mental Status Examination Findings in Depression

Component	Common Findings
Appearance	Disheveled, poor hygiene, unwashed, food-stained clothing
Behavior	Psychomotor retardation; avolition (reduced goal-directed behavior); social isolation
Mood/Affect	Apathy, sadness, flat or blunted affect, dysphoria, crying episodes, labile mood
Speech	Slow, monotone; latency (delayed response to questions)
Thought	Hopelessness, worthlessness, guilt, indecisiveness; recurrent thoughts of death
Sleep	Insomnia (<4 hours or interrupted sleep) OR hypersomnia (14–18 hours/day)
Appetite	Decreased (weight loss) or increased (weight gain)

Critical Findings — Notify Provider Immediately

• Verbal or nonverbal threats of harm to self or others
• Active self-harming behaviors (cutting, picking, head-banging)
• “Cheeking” medications (holding pills in mouth to save for later overdose)
• Suicidal ideation with a specific plan

Screening Tools

• PHQ-9 (Patient Health Questionnaire-9): 9-item validated tool based on DSM-5-TR criteria; scores 0–27; ≥10 = moderate depression; ≥20 = severe depression
• Edinburgh Postnatal Depression Scale: Validated for postpartum depression screening

Depression in Children and Adolescents

• Ask directly about depression when youth are withdrawn or persistently sad for 2 or more weeks.
• Screen for pediatric-specific cues: school inattention, physical complaints (headache/stomachache), self-injury, substance use, and “acting-out” behavior.
• Ask directly about suicide or self-harm after acute interpersonal stressors (for example relationship break-up), because catastrophic interpretation can increase near-term risk.

Pharmacological Treatment

NCLEX Focus

SSRIs are first-line antidepressants. Key nursing priorities: (1) monitor for serotonin syndrome (SSRIs + SNRIs); (2) MAOIs require tyramine-restricted diet (no aged cheese, cured meats, wine); (3) antidepressants take 2–4 weeks to reach therapeutic effect; (4) increased suicide risk in first 2 weeks as energy improves before mood lifts; (5) do NOT abruptly discontinue — taper to prevent discontinuation syndrome.

Drug Class	Examples	Mechanism	Key Side Effects / Nursing Considerations
SSRIs (first-line)	Fluoxetine, Sertraline, Citalopram	Block serotonin reuptake at synapse	Sexual dysfunction, GI upset, insomnia, QTc prolongation; serotonin syndrome (with other serotonergic drugs)
SNRIs	Venlafaxine, Duloxetine	Block serotonin AND norepinephrine reuptake	Similar to SSRIs; also monitor blood pressure; weight gain
TCAs (Tricyclics)	Amitriptyline, Nortriptyline	Block norepinephrine (and partial serotonin) reuptake	Anticholinergic effects (tachycardia, urinary retention, constipation, dry mouth, blurred vision); orthostatic hypotension; lethal in overdose
MAOIs	Phenelzine, Tranylcypromine	Block MAO enzyme → increases serotonin + norepinephrine	Hypertensive crisis with tyramine-rich foods; dangerous drug-drug interactions (avoid SSRIs, meperidine, stimulants)
Atypicals	Bupropion, Mirtazapine, Trazodone	Varied mechanisms	Bupropion: lowers seizure threshold; contraindicated in eating disorders; Mirtazapine: sedation, weight gain
NMDA receptor antagonist (treatment-resistant depression)	Intranasal esketamine	Glutamatergic modulation with rapid antidepressant effect	Often relieves symptoms within hours; given with an oral antidepressant and monitored in a supervised setting

Serotonin Syndrome — Emergency

Occurs when serotonergic medications are combined (e.g., SSRI + SNRI, SSRI + tramadol, SSRI + linezolid):

• Triad: Hyperthermia + neuromuscular abnormality (clonus, hyperreflexia, tremor) + altered mental status
• Action: Discontinue offending medications; supportive care; cyproheptadine (serotonin antagonist)

Non-Pharmacological Treatments

Treatment	Indication
Psychotherapy (CBT, DBT)	Mild-moderate depression; all severity with medication
Electroconvulsive Therapy (ECT)	Severe depression; suicidal patients; medication-resistant depression
Transcranial Magnetic Stimulation (TMS)	Medication-resistant depression; outpatient
Light therapy	Seasonal affective disorder; winter-onset pattern
Exercise and self-care	Adjunct for all severity levels

• Teach clients to avoid self-starting vitamin D or St. John’s wort for depression without provider review because these products are not FDA-approved for depression and may interact with prescribed medications.

Nursing Interventions

• Safety: Assess suicide risk at every encounter; implement falls precautions and environmental safety (remove sharps, ligature risks)
• Therapeutic relationship: Non-judgmental, empathetic communication; use therapeutic communication techniques
• Medication education: Explain 2–4 week onset delay; do not stop abruptly; monitor for side effects; report increased suicidal thoughts during first weeks of therapy
• Activity promotion: Encourage structured activity and exercise; combat anergia and avolition
• Nutrition support: Offer small frequent high-calorie/high-protein snacks and fluids, encourage social mealtimes, and monitor weight trends
• Sleep-rest support: Promote daytime activation and out-of-bed routine, then reinforce evening relaxation and caffeine avoidance
• Elimination support: Track bowel patterns and use hydration, fiber, activity, and bowel-regimen plans to prevent constipation/impaction
• Self-care support: Use step-by-step cueing for hygiene and grooming when psychomotor slowing or poor concentration limits task sequencing
• Interprofessional collaboration: Coordinate with psychiatrists, psychologists, social workers; refer to community mental health resources

Postpartum Psychosis Is an Emergency

Delusions, hallucinations, mania, paranoia, or severe confusion after delivery can indicate postpartum psychosis. Activate immediate emergency escalation (911/ED).

Related Concepts

• antidepressants — Pharmacological management of depression; SSRIs, SNRIs, TCAs, MAOIs drug classes.
• self-harm-and-suicide — Suicide risk assessment and safety planning are priorities in depressive disorder care.
• mental-health-and-mental-illness — Depression as one of the most common and treatable mental health disorders.
• therapeutic-communication — Therapeutic relationship and empathetic communication are foundational to nursing care for depressed clients.
• psychotropic-medications — Psychopharmacology overview including antidepressants in the context of psychiatric nursing.

Self-Check

1. A patient admitted for depression begins a new SSRI. After 5 days, family reports the patient “seems a little more energetic but still talks about wanting to die.” What is the priority nursing concern?
2. A patient on phenelzine (MAOI) asks if they can eat a salami sandwich and have a glass of red wine. How should the nurse respond?
3. What are the three components of serotonin syndrome, and which drug combinations commonly cause it?