Elvitegravir, cobicistat, emtricitabine, and tenofovir and Triamcinolone interaction

Corticosteroids: e.g., betamethasone budesonide ciclesonide dexamethasone fluticasone methylprednisolone mometasone prednisone triamcinolone ↓ elvitegravir ↓ cobicistat ↑ corticosteroids Coadministration with oral dexamethasone or other systemic corticosteroids that induce CYP3A may result in loss of therapeutic effect and development of resistance to elvitegravir.

Consider alternative corticosteroids.

Coadministration with corticosteroids (all routes of administration) whose exposures are significantly increased by strong CYP3A inhibitors can increase the risk for Cushing's syndrome and adrenal suppression.

Alternative corticosteroids including beclomethasone and prednisolone (whose PK and/or PD are less affected by strong CYP3A inhibitors relative to other studied steroids) should be considered, particularly for long-term use.

Co-administration of other strong CYP3A4 inhibitors (e.g., ritonavir, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, saquinavir, telithromycin, cobicistat-containing products) with KENALOG-40 Injection may cause increased plasma concentration of triamcinolone leading to adverse reactions.

CYP3A4 inhibitors: Triamcinolone acetonide is a substrate of CYP3A4.

(See ADVERSE REACTIONS . ) During postmarketing use, there have been reports of clinically significant drug interactions in patients receiving triamcinolone acetonide and strong CYP3A4 inhibitors (e.g., ritonavir).