Lamotrigine Dose Escalation from 25mg
After completing 4 weeks at 25mg daily, increase lamotrigine to 50mg daily, then continue gradual titration by 25-50mg every 1-2 weeks as tolerated. 1
Standard Titration Schedule
- Week 1-4: Continue 25mg daily (current dose) 1
- Week 5-6: Increase to 50mg daily 1
- Week 7 onward: Increase by 25-50mg increments every 1-2 weeks as tolerated 1
- Target maintenance dose: 200mg daily, typically achieved over a 6-week titration period from initiation 2, 3
Critical Titration Considerations
The slow titration schedule is mandatory to minimize the risk of serious rash, including Stevens-Johnson syndrome. 1, 2, 3 The incidence of serious rash is 0.1% when proper titration is followed, but increases substantially with rapid dose escalation. 2, 3
Drug Interaction Adjustments
If taking valproate/valproic acid concurrently:
- Use half the standard lamotrigine doses and slower titration 2, 3, 4
- Valproate increases lamotrigine half-life from 22-37 hours to 48-59 hours 4
If taking enzyme-inducing antiepileptics (carbamazepine, phenytoin, phenobarbital):
- May require higher lamotrigine doses and faster titration 2, 3, 4
- These drugs reduce lamotrigine half-life to 13.5-15 hours 4
Administration Details
- Swallow regular tablets whole with water 1
- Dissolving tablets available for patients with swallowing difficulties 1
- Can be taken with or without food 4
Monitoring for Rash
Stop lamotrigine immediately if any rash develops and do not rechallenge, as lamotrigine is contraindicated in patients with previous lamotrigine-induced rash. 1 The risk is highest during the first 8 weeks of treatment, particularly weeks 2-8. 2, 3