Table 4 Antipsychotic 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 |
|---|---|---|
Aripiprazole (CYP3A4, 2D6) | Potential for ↑ aripiprazole concentrations | Use combination with caution, and monitor for aripiprazole-related toxicity (sedation, sinus tachycardia, nausea/vomiting, or dystonic reactions). Consider starting with a decreased aripiprazole dose or select an alternate agent. |
Asenapine (UGT1A4, CYP1A2) | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response [76]. |
Clozapine (CYP1A2> 3A4,P-gp) | Potential for ↑ clozapine concentrations | Clozapine has a narrow therapeutic index. Use combination with caution, and monitor for clozapine-related toxicity (Bone marrow suppression, generalized seizures, severe sedation, confusion and delirium). Consider starting with a decreased clozapine dose or select an alternate agent. When available, clozapine therapeutic drug monitoring is recommended [77, 78]. |
Olanzapine (CYP1A2, UGT,PGP>2D6) | No interaction expected based on known pharmacologic characteristics | Monitor and titrate dose according to clinical response. |
Paliperidone Primarily renally excreted (59%); minor CYP dependant pathway (CYP3A4, PGP>2D6), but may not be clinically significant. Substrate and inhibitor of P-gp [79] | Potential for ↑ paliperidone concentrations | DAAs inhibit both CYP3A4 and P-gp, and clinically significant interaction, although unlikely, cannot be ruled out. Use combination with caution, and monitor for possible paliperidone-related toxicity. |
Quetiapine (CYP3A4>2D6, P-gp) | Potential for ↑ quetiapine concentrations | Use combination with caution, and monitor for quetiapine-related toxicity (excessive sedation). Consider starting with a decreased quetiapine dose or select an alternate agent [80]. |
Risperidone (CYP2D6, P-gp>3A4) | Potential for ↑ risperidone concentrations | Unlike its active metabolite paliperidone, risperidone is primarily metabolized by CYP2D6. However, the elimination of paliperidone may be impaired. Use combination with caution, and monitor for possible risperidone-related toxicity. |
Ziprasidone (CYP3A4>1A2) Minor CYP dependant pathway (33%) [78]. | Potential for ↑ ziprasidone concentrations | Although clinically significant interaction unlikely, use combination with caution, and monitor for possible ziprasidone-related toxicity (QTc). |