Описание
Valproic acid doubles lamotrigine plasma concentrations by inhibiting its glucuronidation; the combination is associated with Stevens-Johnson syndrome and toxic epidermal necrolysis.
Механизм
Valproic acid inhibits UGT1A4 and UGT2B7, the primary enzymes for lamotrigine glucuronidation, substantially reducing lamotrigine clearance and elevating systemic exposure.
Клиническое значение
The risk of life-threatening skin reactions (SJS/TEN) is significantly increased; the FDA mandates a slower lamotrigine titration schedule when co-prescribed with valproate.
Тактика ведения
Use the specific lamotrigine titration schedule for valproate co-therapy (half the usual starting dose and titration rate); monitor skin closely.
Медицинский отказ от ответственности
This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making medication decisions.