Table 3 Anticonvulsant drug interactions with DAAs
From: Psychiatric treatment considerations with direct acting antivirals in hepatitis C
Drug (route of metabolism) | Known or potential interactions with DAAs | Comments |
|---|---|---|
Lithium (renal) | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response and serum levels. |
Valproic Acid, divalproex Parent: UGT (50%), minor CYP dependent oxidation pathway (<10%) Inhibitor of UGT,CYP2C9/19 | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response and serum levels. |
Carbamazepine Parent: CYP3A>> 2C8, 1A2 Inducer of CYP3A, 2C9, 2C19, UGT and possibly 1A2 | Potential for ↓ DAAs concentrations | Carbamazepine is contraindicated with boceprevir [19] Co-administration of telaprevir with potent CYP3A4 inducers such as carbamazepine may lead to reduced DAA plasma concentrations and decreased efficacy [18] Carbamazepine clearance can also potentially be decreased [62]. Consider an alternate agent with non-inducing metabolic properties. |
Oxcarbazepine Parent: UGT Inhibitor of CYPC19; Potent inducer of CYP3A4. Relative to carbamazepine, oxcarbazepine inducing effect is 54% lower [63] | Potential for ↓ DAAs concentrations | Co-administration of boceprevir and telaprevir with potent CYP3A4 inducers, may lead to reduced DAA plasma concentrations and decreased efficacy. Consider an alternate agent with non-inducing metabolic properties [64]. |
Lamotrigine (UGT) | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response. |
Gabapentin (Renal) | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response. |
Pregabalin (Renal) | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response. |