Major
Carbamazepine × Quetiapine
Antiepileptics. Carboxamide derivatives×Atypical antipsychotics
Mechanism
Carbamazepine is a potent CYP3A4 inducer. Quetiapine plasma levels fall by 75–85%, which can cause loss of therapeutic effect (psychosis or mania relapse).
Symptoms
Return of positive symptoms: hallucinations, delusions, agitation. In bipolar disorder: manic episode risk.
Management
During carbamazepine therapy, increase quetiapine 4- to 5-fold with clinical monitoring. Alternative anticonvulsants without induction: sodium valproate, lamotrigine, or levetiracetam.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.