How do I restart Luvox (fluvoxamine) after a 1-month cessation in a patient previously taking 50mg daily?

Restarting Fluvoxamine After a One-Month Cessation

When restarting fluvoxamine after a one-month cessation in a patient previously on 50mg daily, begin with 25mg daily for the first week, then increase to 50mg daily, administering the dose at bedtime to minimize side effects.

Recommended Restart Protocol

The FDA-approved labeling for fluvoxamine provides clear guidance on dosing that can be applied to patients restarting therapy:

1. Initial restart dose: 25mg once daily at bedtime
2. Titration schedule: Increase to 50mg after 7 days
3. Administration timing: Give as a single daily dose at bedtime to minimize daytime side effects

This gradual approach is recommended because:

• Complete washout has likely occurred after one month (fluvoxamine has a half-life of 12-15 hours) 1
• Starting at a lower dose reduces the risk of side effects that might affect adherence
• Bedtime administration helps manage common side effects like nausea and drowsiness 2

Pharmacokinetic Considerations

Fluvoxamine has several pharmacokinetic properties that support a gradual restart approach:

• Steady-state plasma concentrations are achieved within 5-10 days after initiation 1
• The drug displays nonlinear pharmacokinetics at therapeutic doses, with disproportionally higher plasma concentrations at higher doses 1
• First-pass hepatic metabolism results in approximately 50% bioavailability 1

Monitoring for Adverse Effects

During the restart period, monitor for:

• Common side effects: Nausea, dry mouth, drowsiness, insomnia, dizziness 3
• Discontinuation symptoms: Dizziness/incoordination, headaches, nausea, and irritability have been reported with abrupt discontinuation 4

Special Considerations

For Elderly Patients or Those with Hepatic Impairment

• Consider an even more gradual titration schedule
• The FDA label specifically notes: "Elderly patients and those with hepatic impairment have been observed to have a decreased clearance of fluvoxamine maleate" 2

For Patients with Anxiety Disorders

• The therapeutic effect may take several weeks to manifest
• Maintaining the restart schedule is important even if immediate symptom relief is not observed

Long-term Management

Once the patient has stabilized on the 50mg daily dose:

• Assess response after 4-6 weeks
• If response is inadequate, consider increasing the dose in 50mg increments every 4-7 days as tolerated
• Maximum recommended dose is 300mg daily for adults 2
• Doses above 100mg should be given in two divided doses, with the larger dose at bedtime 2

Avoiding Common Pitfalls

1. Avoid starting at the full previous dose - This increases the risk of side effects that may lead to discontinuation
2. Don't skip the titration period - Even though the patient was previously on fluvoxamine, their body needs time to readjust
3. Be aware of drug interactions - Fluvoxamine inhibits several CYP enzymes (particularly CYP1A2) and can interact with many medications 1
4. Don't discontinue abruptly in the future - If discontinuation is needed, implement a gradual taper to minimize withdrawal symptoms 2, 4

By following this structured approach to restarting fluvoxamine, you can maximize the chances of successful treatment resumption while minimizing adverse effects.