nefazodone

Quick answers

• What is nefazodone?

  Nefazodone (brand Serzone; generics) is an antidepressant indicated for depression (label). Its mechanism includes serotonin uptake inhibition with 5-HT2 antagonism and α1 antagonism, contributing to a relatively less activating clinical profile for some patients (mechanism/clinical).

• What is Serzone?

  Serzone is a brand name for nefazodone.

• What is Serzone (nefazodone) used for?

  Label indications include: Depression (label).

• What drug class is Serzone (nefazodone)?

  Serotonin antagonist and reuptake inhibitor (SARI-like): inhibits serotonin/norepinephrine uptake with 5-HT2 and α1 antagonism; notable for rare but life-threatening hepatic failure and strong CYP3A4 inhibition.

• What strengths does Serzone (nefazodone) come in?

  Oral tablets (label): 50 mg, 100 mg, 150 mg, 200 mg, 250 mg.

Snapshot

• Class: Adjunctive therapy
• Common US brands: Serzone
• Therapeutic drug monitoring not routinely recommended.
• Last reviewed: 2025-12-30

Clinical Highlights

Nefazodone (brand Serzone; generics) is an antidepressant indicated for depression (label). Its mechanism includes serotonin uptake inhibition with 5-HT2 antagonism and α1 antagonism, contributing to a relatively less activating clinical profile for some patients (mechanism/clinical). The defining safety issue is rare but potentially life-threatening hepatic failure. Labeling highlights a reported U.S. rate of roughly one case of liver failure resulting in death or transplant per 250,000 to 300,000 patient-years and advises weighing this risk when selecting among alternatives (label).

Dosing & Formulations

Oral tablets (label): 50 mg, 100 mg, 150 mg, 200 mg, 250 mg. Label initiation is typically 200 mg/day divided BID, with titration toward 300–600 mg/day as tolerated; dose increases are commonly spaced at one-week intervals in labeling (label).

Monitoring & Risks

Boxed warning: antidepressants increase risk of suicidal thoughts and behaviors in children, adolescents, and young adults; close monitoring early in treatment is typical (label). Hepatic failure risk is the key safety differentiator. Labeling advises avoiding initiation in active liver disease and discontinuing with clinical signs of liver injury or significant transaminase elevations (label).

Drug Interactions

Nefazodone is a strong CYP3A4 inhibitor; many interactions are driven by increased exposure to co-prescribed CYP3A4 substrates (label). Labeling lists contraindications with certain medications that rely on CYP3A4 for clearance (e.g., triazolam) because of risk of excessive sedation/respiratory depression and other serious outcomes (label).

Practice Notes

Because of hepatic failure risk and interaction burden, nefazodone is typically reserved for select cases where alternatives have failed or were poorly tolerated (label/clinical). If liver injury symptoms emerge (e.g., fatigue, anorexia, dark urine, jaundice), clinicians typically stop the medication promptly and evaluate liver tests (label/clinical).

References

1. Nefazodone hydrochloride tablets prescribing information — DailyMed (2025)
2. APA Clinical Practice Guideline for the Treatment of Depression — American Psychiatric Association (2023)Guidelinedepressionclinical
3. CANMAT 2024 Clinical Guidelines for Major Depressive Disorder — Canadian Journal of Psychiatry (2024)
4. Consensus Guidelines for Therapeutic Drug Monitoring in Neuropsychopharmacology: Update 2017 — Pharmacopsychiatry (2018)