Maximum Dose of Fluvoxamine
The maximum recommended dose of fluvoxamine is 300 mg per day for adults and adolescents (ages 12-17), and 200 mg per day for children (ages 8-11). 1
Adult Dosing
- Start at 50 mg once daily at bedtime, then increase by 50 mg increments every 4-7 days as tolerated, up to a maximum of 300 mg per day. 1
- Doses above 100 mg per day should be divided into two doses, with the larger dose given at bedtime. 1
- The FDA-approved dosing range for obsessive-compulsive disorder in controlled trials was 100-300 mg/day. 1
- Clinical guidelines from 2002 recommend a maximum of 150 mg twice daily (300 mg total daily dose). 2
Pediatric Dosing (Ages 8-17)
- Children ages 8-11: Start at 25 mg once daily at bedtime, increase by 25 mg increments every 4-7 days, with a maximum of 200 mg per day. 1
- Adolescents ages 12-17: Start at 25 mg once daily at bedtime, increase by 25 mg increments every 4-7 days, with a maximum of 300 mg per day (same as adults). 1
- Doses above 50 mg per day should be divided into two doses, with the larger dose given at bedtime. 1
- Female children may achieve therapeutic effect at lower doses than males. 1
- Pharmacokinetic studies show that steady-state plasma concentrations are 2-3 times higher in children (ages 6-11) compared to adolescents, justifying the lower maximum dose in younger children. 3, 4
Special Populations
- Elderly and hepatically impaired patients: Use lower initial doses and slower titration due to decreased clearance of fluvoxamine. 1
- The FDA label specifically recommends modifying both the initial dose and subsequent titration schedule in these populations. 1
Important Clinical Considerations
- Therapeutic response typically occurs by week 6, with maximal benefit by weeks 10-12 or later. 5
- The American Academy of Child and Adolescent Psychiatry emphasizes close monitoring for suicidality in patients ≤24 years old during the first months and after all dose adjustments. 5
- When discontinuing, taper gradually rather than stopping abruptly to minimize discontinuation syndrome (dizziness, fatigue, myalgias, headaches, nausea, insomnia, sensory disturbances, anxiety, agitation). 5, 1
Beyond Standard Maximum Dosing
- A 2023 case report documented successful remission of treatment-resistant OCD with 600 mg daily (double the FDA-approved maximum), which was well-tolerated for 3 months. 6
- However, this exceeds FDA-approved dosing and should only be considered in exceptional circumstances of treatment-resistant OCD under specialist supervision. 6
Drug Interaction Warning
- Fluvoxamine is contraindicated with MAOIs due to serotonin syndrome risk. 5
- Fluvoxamine is a potent inhibitor of CYP1A2 and moderately inhibits CYP2C19, CYP2C9, CYP3A4, and CYP2D6, requiring caution with concurrent medications. 5, 7
- Exercise particular caution when combining with alprazolam or triazolam, as fluvoxamine significantly increases their levels. 2