Cenobamateinteractions

Phenytoin: Gradually decrease phenytoin dosage by up to 50%.

Phenobarbital and Clobazam: Reduce dosage as needed when used concomitantly with XCOPRI. Lamotrigine, Carbamazepine: Increase dosage as needed when used concomitantly with XCOPRI.

CYP2B6 and CYP3A Substrates: Increase dosage as needed when used concomitantly with XCOPRI.

CYP2C19 Substrates: Reduce dosage as needed when used concomitantly with XCOPRI.

Oral Contraceptives: Effectiveness of hormonal oral contraceptives may be reduced when administered concomitantly with XCOPRI. Women should use additional or alternative non-hormonal birth control.

7.1 Effect of XCOPRI on

Other Drugs Table 5 summarizes the effect of XCOPRI on other drugs.

Table 5: Pharmacokinetic Drug Interactions Drug or Substrate Type Effect of XCOPRI on Drug or Substrate Clinical Recommendation Antiepileptic Drugs lamotrigine ↓ plasma concentrations Because of a potential for reduced efficacy of these drugs, increase the dosage of lamotrigine or carbamazepine, as needed, when used concomitantly with XCOPRI. carbamazepine ↓ plasma concentrations phenytoin ↑ plasma concentrations Because of a potential 2-fold increase in phenytoin levels, gradually decrease phenytoin dosage by up to 50% as XCOPRI is being titrated. phenobarbital ↑ plasma concentrations Because of a potential for an increase in the risk of adverse reactions from these drugs, consider a reduction in dosage of phenobarbital or clobazam, as clinically appropriate, when used concomitantly with XCOPRI. desmethylclobazam, the active metabolite of clobazam ↑ plasma concentrations CYP2B6 Substrates ↓ plasma concentrations Because of a potential for reduced efficacy of these drugs, increase the dosage of CYP2B6 or CYP3A4 substrates, as needed, when used concomitantly with XCOPRI. CYP3A Substrates ↓ plasma concentrations Oral contraceptives ↓ plasma concentrations Because of the potential for reduced efficacy of oral contraceptives, women should use additional or alternative non-hormonal birth control while taking XCOPRI. CYP2C19 Substrates ↑ plasma concentrations Because of a potential for an increase in the risk of adverse reactions from these drugs, consider a reduction in dosage of CYP2C19 substrates, as clinically appropriate, when used concomitantly with XCOPRI.

7.2 Drug that

Shorten the QT Interval XCOPRI can shorten the QT interval; therefore, caution should be used when administering XCOPRI and other drugs that shorten the QT interval.

7.3 CNS Depressants and

Alcohol Concomitant use of XCOPRI with other CNS depressants, including alcohol, may increase the risk of neurological adverse reactions, including sedation and somnolence.