What is the recommended dosing for Luvox (fluvoxamine) in a patient with obsessive-compulsive disorder (OCD)?

Fluvoxamine (Luvox) Dosing for OCD

For adults with OCD, start fluvoxamine at 50 mg once daily at bedtime, then increase by 50 mg every 4-7 days as tolerated up to a target range of 100-300 mg/day, with doses above 100 mg split into two divided doses (larger dose at bedtime). 1

Adult Dosing Algorithm

• Starting dose: 50 mg once daily at bedtime 1
• Titration schedule: Increase by 50 mg increments every 4-7 days as tolerated 1
• Target therapeutic range: 100-300 mg/day 1, 2
• Maximum FDA-approved dose: 300 mg/day 1
• Dose division: Total daily doses >100 mg should be split into two divided doses, with the larger dose given at bedtime 1

Critical timing consideration: Allow a full 8-12 weeks at the maximum tolerated dose before declaring treatment failure, as maximal improvement typically occurs by week 12 or later. 3

Pediatric Dosing (Ages 8-17)

• Starting dose: 25 mg once daily at bedtime 1
• Titration schedule: Increase by 25 mg increments every 4-7 days as tolerated 1
• Maximum dose for children ≤11 years: 200 mg/day 1, 4
• Maximum dose for adolescents 12-17 years: 300 mg/day 1, 4
• Dose division: Total daily doses >50 mg should be split into two divided doses, with the larger dose at bedtime 1
• Important caveat: Female children may achieve therapeutic effect at lower doses than males 1

The pharmacokinetic rationale for lower pediatric dosing is that steady-state plasma concentrations are 2-3 times higher in children aged 6-11 years compared to adolescents, necessitating the 200 mg/day maximum in younger children. 5, 4

Special Populations

Elderly or hepatically impaired patients require modified initial dosing and slower titration due to decreased fluvoxamine clearance. 1 Start at lower doses (25 mg daily) and increase more gradually than in younger adults.

Treatment Duration and Maintenance

• Minimum treatment duration after remission: 12-24 months due to high relapse risk after discontinuation 3, 6
• Maintenance strategy: Use the lowest effective dose and periodically reassess the need for continued treatment 1
• Long-term efficacy: Improvements with fluvoxamine have been observed for up to 1 year in pediatric patients with OCD 5, 4

Expected Response Timeline

• Early response indicator: Improvement by weeks 2-4 predicts ultimate treatment success 3
• Clinically significant improvement: Typically by week 6 6
• Maximal improvement: Week 12 or later 3, 6
• Minimum adequate trial: 8-12 weeks at maximum tolerated dose before considering treatment failure 3, 6

Efficacy Data

In controlled trials, fluvoxamine 100-300 mg/day for 6-10 weeks produced response rates of 38-52% compared to 0-18% with placebo. 2 In pediatric patients, 33.3% of fluvoxamine-treated patients versus 9.0% on placebo were classified as "responders" (much or very much improved). 7

Common Adverse Effects

The most frequently reported adverse events include nausea (>10% of patients), somnolence, asthenia, headache, dry mouth, and insomnia. 2 In pediatric patients, abdominal discomfort occurs more frequently with fluvoxamine than placebo, though most other adverse events occur at similar rates. 5, 4

Drug Interaction Considerations

Exercise caution when combining fluvoxamine with alprazolam or triazolam due to significant pharmacokinetic interactions. 8 Fluvoxamine is a potent inhibitor of CYP1A2, moderate inhibitor of CYP2C19 and CYP3A4, and weak inhibitor of CYP2D6. 2

Discontinuation Strategy

When discontinuing fluvoxamine, use gradual dose reduction rather than abrupt cessation to minimize withdrawal symptoms. 1 If intolerable symptoms occur after dose reduction, resume the previous dose and taper more gradually. 1

Treatment Resistance Options

If inadequate response after 8-12 weeks at maximum tolerated dose, consider: switching to another SSRI, trying clomipramine (150-250 mg/day), augmenting with atypical antipsychotics (aripiprazole 10-15 mg or risperidone), or adding cognitive-behavioral therapy with exposure and response prevention (ERP), which has larger effect sizes than medication augmentation alone. 3, 6

High-Dose Considerations

While the FDA-approved maximum is 300 mg/day 1, one case report documented remission with 600 mg/day fluvoxamine in treatment-resistant OCD, though this exceeds standard recommendations and requires careful monitoring. 9 This should only be considered in truly refractory cases under specialist supervision.