Fluvoxamine

SSRI (Sigma-1)·Psychiatry - Antidepressants

Obsessive-Compulsive Disorder, Major Depressive Disorder

Authority requiredPBSSSRILuvox, Faverin50 mg tablet+2

Max Dose

300 mg/day

Half-life

15 h

CYP Inhibitor

CRITICAL

OCD

GOLD STANDARD

Rapid Summary

Overview

Unique SSRI with potent Sigma-1 receptor agonism. The gold standard for severe Obsessive-Compulsive Disorder (OCD). However, it is an incredibly dangerous inhibitor of liver enzymes.

Maximum Dose

Max 300 mg/day (given in divided doses).

Clinical Focus

Completely shuts down CYP1A2. Fatal interaction with Clozapine, Agomelatine, and Theophylline.

Bottom Line

Fluvoxamine is an SSRI primarily used for OCD with potent CYP1A2 inhibition, but has significant drug interactions (especially with clozapine and theophylline) and more GI side effects than other SSRIs.

Formulation & Access

Brand Names

Luvox, Faverin

Oral Routes

Tablets (50 mg, 100 mg).

Prescribing & PBS

Authority Required (PBS) for OCD/Depression.

Indications & Use

Primary

PBSTGA

Obsessive-Compulsive Disorder, Major Depressive Disorder.

Clinical Place

Niche use for severe OCD. Largely avoided for simple depression due to terrifying drug interaction profile.

Quick reference

Class & Role

SSRI (Sigma-1) — Unique SSRI with potent Sigma-1 receptor agonism.

Route / Formulation

Tablets (50 mg, 100 mg). (Luvox, Faverin)

Usual Dose & Max

Start PO 50 mg NOCTE. Titrate up to 100-300 mg/day. Doses > 150 mg should be divided BD. Max 300 mg/day (given in divided doses).

Key Indication Doses

Obsessive-Compulsive Disorder: Start PO 50 mg NOCTE. Titrate up to 100-300 mg/day. Doses > 150 mg should be divided BD. Depression: Start PO 50 mg NOCTE. Target 100-200 mg/day.

Best Uses

Avoid / Cautions

Concurrent use of MAOIs, Tizanidine, Agomelatine, or Tizanidine. Avoid concurrent Clozapine without specialist monitoring. Pregnancy Category B2.

Key Risks

Gastrointestinal: Nausea and vomiting (Higher rate than most other SSRIs, usually transient). Neurological: Sedation (Unlike Fluoxetine which is activating, Fluvoxamine is mildly sedating, hence NOCTE dosing). Metabolic: Hyponatremia (SIADH).

Key Interactions

Absolute blockade of CYP1A2 and CYP2C19. If given to a patient on Clozapine, Clozapine levels will skyrocket by 500-1000%, causing fatal seizures and coma. If given to a patient on Duloxetine or Agomelatine, severe liver toxicity ensues.

Monitoring

Run a comprehensive drug-interaction check before prescribing this drug. Routine U&E (sodium).

Clinical Pearl

While Sertraline and Fluoxetine treat OCD, Fluvoxamine is universally regarded by psychiatrists as the most potent agent for crippling, treatment-resistant OCD due to the unique Sigma-1 action.

Access

Authority requiredLuvox, Faverin50 mg tablet

Brand: Luvox, Faverin
PBS status: Authority required
Formulation: Tablets (50 mg, 100 mg)