What is the usual dosing range for Luvox (fluvoxamine) in adults, children, and elderly patients?

Normal Dosing for Luvox (Fluvoxamine)

The FDA-approved starting dose for fluvoxamine in adults is 50 mg once daily at bedtime, with titration in 50 mg increments every 4-7 days up to a maximum of 300 mg/day for obsessive-compulsive disorder. 1

Adult Dosing

Standard Dosing Regimen:

• Starting dose: 50 mg once daily at bedtime 1
• Titration: Increase by 50 mg every 4-7 days as tolerated 1
• Therapeutic range: 100-300 mg/day 1
• Maximum dose: 300 mg/day 1, 2
• Divided dosing: Total daily doses exceeding 100 mg should be split into two divided doses, with the larger dose given at bedtime 1

Clinical Context:

• For depression, the effective dose range is typically 100-150 mg/day, with 73.7% of patients showing improvement at higher doses (100-150 mg) versus 47.1% at lower doses (50-75 mg) 3
• For OCD and anxiety disorders, doses of 100-300 mg/day are standard 4, 5
• The American Family Physician guidelines recommend 50 mg twice daily with a maximum of 150 mg twice daily (300 mg total) 5, 2

Pediatric Dosing (Ages 8-17)

Starting dose: 25 mg once daily at bedtime 1

• Titration: Increase by 25 mg every 4-7 days as tolerated 1
• Children (up to age 11): Maximum 200 mg/day 1, 6, 7
• Adolescents (12-17 years): Maximum 300 mg/day 1, 6, 7
• Divided dosing: Total daily doses exceeding 50 mg should be split into two divided doses, with the larger dose at bedtime 1

Pharmacokinetic Rationale:

• Steady-state plasma concentrations are 2-3 times higher in children (ages 6-11) compared to adolescents, justifying the lower maximum dose of 200 mg/day in younger children 6, 7
• Absorption in adolescents is similar to adults, supporting the 300 mg/day maximum in this age group 6, 7

Elderly and Hepatically Impaired Patients

Modified dosing is required due to decreased clearance of fluvoxamine in these populations 1

• Start with lower initial doses 1
• Use slower titration schedules 1
• Monitor closely for adverse effects 1

Time to Therapeutic Response

• Initial response: Typically by week 6 2
• Maximal benefit: Weeks 10-12 or later 2
• Adequate trial duration: At least 6 weeks at therapeutic doses, with >80% of responders showing improvement by this timepoint 3
• For OCD specifically, 8-10 weeks at maximum tolerated dose is needed before declaring treatment failure 2

Critical Safety Considerations

Suicidality Monitoring:

• Close monitoring is mandatory in patients ≤24 years old during initial months and after all dose adjustments 2, 1
• Contact patients shortly after initiation to assess adherence, status, and adverse events 2
• Starting at higher than recommended doses increases risk of deliberate self-harm and suicide-related events 2

Discontinuation:

• Never stop abruptly - taper gradually over 1-2 weeks to minimize discontinuation syndrome 2, 1
• Discontinuation syndrome includes dizziness, fatigue, myalgias, headaches, nausea, insomnia, sensory disturbances, anxiety, and agitation 2

Drug Interactions:

• Absolute contraindication: MAOIs due to serotonin syndrome risk 2, 5
• Potent CYP1A2 inhibitor and moderate inhibitor of CYP2C19, CYP2C9, CYP3A4, and CYP2D6 2, 4
• Exercise particular caution when combining with alprazolam or triazolam - fluvoxamine significantly increases their levels and requires 50% dose reduction of these benzodiazepines 5, 2
• Avoid co-administration with QT-prolonging drugs 2

Serotonin Syndrome:

• Monitor for confusion, agitation, tremor, clonus, hyperreflexia, muscle rigidity, and autonomic instability, especially within 24-48 hours after dose changes or when combined with other serotonergic agents 2

Common Adverse Effects

• Most common: Nausea (>10% of patients), somnolence, asthenia, headache, dry mouth, insomnia 4
• General SSRI effects: Sweating, tremors, nervousness, gastrointestinal disturbances, sexual dysfunction 5
• Fluvoxamine has fewer anticholinergic and cardiovascular effects compared to tricyclic antidepressants 4, 8