Medications for Severe Depression with Anhedonia

First-Line Antidepressants

• Standard first line for MDD, but patients with melancholic features (specifically anhedonia + mood non-reactivity) may respond less well to SSRIs/SNRIs compared to those with non-melancholic presentations.
• Some anhedonia relief occurs as part of global depression improvement, but serotonin-dominant mechanisms have limited direct reward-pathway action.

• Norepinephrine reuptake blockade adds an activating dimension; levomilnacipran has the strongest NE selectivity among SNRIs.

• Predominantly noradrenergic and dopaminergic reuptake inhibitor - makes it the most rationally targeted first-line agent specifically for anhedonia and motivational deficits.
• Described as an "activating antidepressant" - frequently prescribed in combination with a more sedating 5HT agent (e.g., bupropion + SSRI).
• Also approved for smoking cessation.

• The 5-HT2C antagonism facilitates dopamine and norepinephrine release in the prefrontal cortex, which is specifically noted to account for its favorable effect on anhedonia and minimal sexual side effects.
• Monitor liver function (hepatic enzyme elevation risk).
• Not available in the US but widely used in Europe.
• Kaplan & Sadock's Comprehensive Textbook of Psychiatry, p. 5152

• Alpha-2 antagonist - promotes 5HT and NE release; sedating profile useful for depression with severe insomnia and weight loss.

Augmentation Strategies for Anhedonia-Dominant or Treatment-Resistant Depression

Atypical Antipsychotics (SGAs) - dopamine D2/D3 modulation

• Kaplan & Sadock's Comprehensive Textbook of Psychiatry, p. 5154

Lithium

• Augments TCAs and SSRIs; two recent meta-analyses support efficacy.
• Doses varied (250-1,200 mg/day); modest remission benefit at STAR*D level 3.
• Requires monitoring of serum levels, renal and thyroid function.

Triiodothyronine (T3) 25-50 mcg/day

• Modest augmentation benefit; comparable to lithium at STAR*D level 3.

Rapid-Acting Agents - Particularly Relevant for Severe Anhedonia

Ketamine / Esketamine (Spravato)

• Mechanism: NMDA receptor antagonist - disinhibits glutamate release from GABAergic interneurons, causing an acute cortical glutamate surge, AMPA receptor activation, downstream synaptogenesis and neuroplastic effects.
• Onset: Antidepressant effect within hours, peaking at 3 days. This is distinct from the 2-6 week onset of standard antidepressants.
• Anhedonia evidence: A 2024 systematic review (22 studies including 4 RCTs) found that all studies reported alleviation of anhedonia following ketamine or esketamine administration, regardless of number of infusions. Neuroimaging data confirmed ketamine's neuroplastic effects on reward circuitry (PMID: 38917771).
• IV ketamine (0.5 mg/kg over 40 min) - off-label, gold standard route; most evidence; generally as effective as ECT.
• Intranasal esketamine (Spravato) - FDA-approved for TRD (+ oral antidepressant); superior to quetiapine augmentation in a 2023 RCT.
• Adverse effects: Dissociation, perceptual distortions, potential laryngospasm - requires supervised in-clinic administration for 2 hours post-dose. Abuse potential is a consideration.
• Maudsley Prescribing Guidelines, p. 382

Third-Line and Special Contexts

• Historically particularly effective for melancholic depression with anhedonia.
• Now third-line due to cardiac toxicity, anticholinergic effects, and lethality in overdose.
• Amitriptyline was among the most effective antidepressants in the landmark 21-drug network meta-analysis (116,500 participants).

• Traditionally thought best for atypical depression (mood reactivity preserved), not melancholic features.
• Now rarely used due to dietary tyramine restrictions and drug interactions.
• Irreversible MAOIs retain a role in truly refractory cases.

• Reported useful as augmentation in antidepressant therapy and in medication-resistant bipolar II depression. Directly targets dopaminergic reward circuits - rationally targets anhedonia.
• Kaplan & Sadock's Synopsis of Psychiatry

• A randomized trial showed psilocybin (25 mg single dose + psychotherapy) was comparable to escitalopram in reducing depression, with rapid onset and effects lasting up to 3 months.
• Expanded trials ongoing; not yet standard of care.

• Response rates up to 70% in antidepressant-refractory cases.
• Specifically indicated for severe depression with acute suicidality, psychotic features, or food refusal.
• Ketamine appears broadly as effective as ECT for TRD.

Anti-Inflammatory Approach (Emerging)

Practical Algorithm Summary

Severe MDD with prominent anhedonia
         |
1st line → Bupropion (or + SSRI) | Agomelatine | SNRI
         |  (if inadequate at 4-6 weeks)
2nd line → Add SGA (aripiprazole, brexpiprazole, quetiapine)
         | OR add lithium / T3
         |  (if still refractory = TRD)
3rd line → IV ketamine / intranasal esketamine
         | TCA (amitriptyline, nortriptyline)
         | Dopamine agonist augmentation (pramipexole)
         | MAOI
         |  (if multiple drug failures)
Biological → ECT (esp. with psychosis or suicidality)
             rTMS (adjunctive evidence)
             Psilocybin (investigational)
Inflammatory subtype → Anti-inflammatory agents (if CRP ≥ 2)

• Kaplan & Sadock's Comprehensive Textbook of Psychiatry (antidepressant treatment strategies, pp. 5146-5154)
• Maudsley Prescribing Guidelines in Psychiatry, 15th ed. (ketamine, p. 382)
• Kwasny et al. 2024, Eur Neuropsychopharmacol - ketamine for anhedonia systematic review [PMID: 38917771]
• Mac Giollabhui et al. 2026, Am J Psychiatry - anti-inflammatory treatment meta-analysis [PMID: 41366844]