Lamotrigine Discontinuation Titration Schedule
When discontinuing lamotrigine 300mg daily, the dose should be gradually tapered over 4 weeks, reducing by 25-33% of the original dose every week to minimize withdrawal symptoms and potential seizure risk.
Recommended Discontinuation Schedule
For a patient on lamotrigine 300mg daily:
Week 1:
- Reduce to 200mg daily (approximately 33% reduction)
Week 2:
- Reduce to 150mg daily (50% of original dose)
Week 3:
- Reduce to 100mg daily
Week 4:
- Reduce to 50mg daily
Week 5:
- Discontinue completely
Rationale for Gradual Discontinuation
The need for gradual discontinuation is based on several important clinical considerations:
Risk of Withdrawal Symptoms: Rapid discontinuation of lamotrigine has been associated with withdrawal symptoms including:
- Psychomotor inhibition
- Anhedonia
- Tremor
- Tachycardia
- Hyperhydrosis 1
Seizure Risk: Abrupt discontinuation may increase the risk of seizures, even in patients taking lamotrigine for mood disorders rather than epilepsy.
Neurochemical Adaptation: Lamotrigine affects voltage-sensitive sodium channels and inhibits the release of glutamate and aspartate 2. The brain requires time to readjust to the absence of these effects.
Special Considerations
Concomitant Medications: If the patient is also taking valproate, the discontinuation schedule may need to be even more gradual due to pharmacokinetic interactions 3.
Monitoring: During the tapering period, monitor for:
- Emergence of mood symptoms (especially depression)
- Withdrawal symptoms
- Seizure activity
Patient Education: Inform patients about potential withdrawal symptoms and instruct them to report any concerning symptoms immediately.
Alternative Approaches
For patients at higher risk of adverse effects from discontinuation (history of severe mood instability, seizures, or previous difficult medication withdrawals), an even more gradual taper might be considered:
- 6-8 week taper with 25% reductions every 2 weeks
- Weekly reductions of smaller increments (e.g., 50mg per week)
Cautions
Avoid Rapid Discontinuation: Evidence suggests that rapid discontinuation of lamotrigine can lead to withdrawal syndromes 1.
Individual Variation: While this schedule is appropriate for most patients, clinical judgment should be used to adjust the tapering schedule based on individual patient response and risk factors.