Carbamazepine

Carbamazepine and phenytoin have complex bidirectional interactions that can alter plasma levels of either drug in unpredictable ways.

Carbamazepine reduces valproic acid levels through enzyme induction, while valproic acid inhibits epoxide hydrolase, increasing the toxic carbamazepine-10,11-epoxide metabolite.

Carbamazepine reduces topiramate plasma concentrations by approximately 40% through enzyme induction, potentially impairing seizure control.

Carbamazepine significantly reduces venlafaxine plasma concentrations through CYP3A4 induction, potentially reducing antidepressant efficacy.

Carbamazepine may reduce levodopa efficacy through enzyme induction and pharmacodynamic antagonism, potentially worsening Parkinson's disease control.

Carbamazepine reduces omeprazole plasma concentrations through CYP3A4 induction, potentially reducing the efficacy of acid suppression therapy.

Carbamazepine is a potent CYP3A4 inducer that markedly increases dexamethasone clearance, reducing its plasma concentrations by 50–80% and risking loss of anti-inflammatory and immunosuppressive efficacy.

Carbamazepine, a potent enzyme inducer, significantly reduces sertraline plasma concentrations, potentially impairing antidepressant efficacy.

Carbamazepine substantially reduces duloxetine plasma levels through CYP1A2 and CYP3A4 induction, risking loss of antidepressant efficacy.

Carbamazepine reduces lamotrigine plasma concentrations by approximately 50% through enzyme induction, requiring lamotrigine dose adjustment.

Carbamazepine induces hepatic CYP enzymes involved in thyroid hormone metabolism, increasing levothyroxine clearance and potentially causing hypothyroid relapse in patients on replacement therapy.

Carbamazepine induces CYP enzymes that convert acetaminophen to its hepatotoxic metabolite NAPQI, increasing the risk of acetaminophen-induced liver injury even at therapeutic doses.