Interacting drugs | Effects (probable mechanism) | Management |
Carbamazepine, with: | ||
Brivaracetam | Possible carbamazepine toxicity (decreased metabolism of active epoxide metabolite¶) | Monitor clinical status; reduction of carbamazepine dose may be needed |
Decreased brivaracetam effect (increased metabolism by CYP2C19) | Monitor clinical status; brivaracetam dose may need to be adjusted | |
Clonazepam | Decreased clonazepam effect (increased metabolism by CYP3A4) | Monitor clinical status |
Felbamate | Possible carbamazepine toxicity (increased concentration of active epoxide metabolite¶) | Monitor clinical status; felbamate and carbamazepine dose may need to be adjusted |
Decreased felbamate effect (increased metabolism by CYP3A4) | A reduction in carbamazepine dose is recommended when felbamate is added to carbamazepine therapy. Specific dose adjustment recommendations are provided in the drug monograph included within UpToDate. | |
Lamotrigine | Carbamazepine toxicity (increased concentration of active epoxide metabolite¶) | Monitor clinical status; serum carbamazepine measurements alone may not predict toxicity |
Decreased lamotrigine effect (increased metabolism; glucuronidation) | Monitor clinical status and lamotrigine concentrations; lamotrigine dose may need to be increased. Specific lamotrigine dose adjustment recommendations are provided in the drug monograph included within UpToDate. | |
Levetiracetam | Possible increased risk of carbamazepine toxicity (mechanism not established) | Monitor for clinical evidence of carbamazepine toxicity |
Possible decreased levetiracetam concentrations (increased metabolism) | Monitor clinical effect | |
Perampanel | Decreased perampanel effect (increased metabolism by CYP3A4) | Monitor clinical status; perampanel dosage may need to be adjusted |
Phenytoin | Decreased carbamazepine effect (increased metabolism) | Monitor clinical status and carbamazepine and phenytoin concentrations |
Altered phenytoin effect may include decreased or increased phenytoin levels (mechanism not established) | ||
Tiagabine | Decreased tiagabine effect (increased metabolism by CYP3A4) | Monitor clinical status |
Topiramate | Possible decreased topiramate effect (increased metabolism); possible additive CNS side effects (mechanism not established) | Monitor clinical status; may need higher doses of topiramate |
Valproate | Decreased valproate effect and possible increased toxicity (increased metabolism by CYP 2C9, 2C19, glucuronidation, and formation of toxic metabolite) | Monitor clinical status and valproate concentrations |
Carbamazepine toxicity (increased concentration of active epoxide metabolite¶ and displacement from binding sites) | Monitor clinical status, carbamazepine, and carbamazepine epoxide concentrations; carbamazepine dose may need to be adjusted | |
Zonisamide | Decreased zonisamide effect (increased metabolism by CYP3A4) | Monitor zonisamide concentrations and clinical status; zonisamide dosage may need to be adjusted |
CYP: cytochrome P450.
* Not all potential interactions are listed. Additional interactions of antiseizure medications and management suggestions may be determined by using the drug interactions program included within UpToDate.
¶ Routine carbamazepine serum measurements do not assess for accumulation of the active carbamazepine-epoxide metabolite, but this metabolite can be measured as a separate test; refer to accompanying text.Do you want to add Medilib to your home screen?