OBJECT DRUGS

• Eplerenone (Inspra)

PRECIPITANT DRUGS

Enzyme Inhibitors:

• Amiodarone (Cordarone, etc.)
• Amprenavir (Agenerase)
• Aprepitant (Emend)
• Atazanavir (Reyataz)
• Boceprevir (Victrelis)
• Ceritinib (Zykadia)
• Cobicistat (Stribild)
• Conivaptan (Vaprisol)
• Cyclosporine (Neoral, etc.)
• Darunavir (Prezista)
• Delavirdine (Rescriptor)
• Diltiazem (Cardizem, etc.)
• Dronedarone (Multaq)
• Grapefruit
• Imatinib (Gleevec)
• Indinavir (Crixivan)
• Lapatinib (Tykerb)
• Lomitapide (Juxtapid)
• Mifepristone (Korlym)
• Nelfinavir (Viracept)
• Ritonavir (Norvir)
• Saquinavir (Invirase)
• Telaprevir (Incivek)
• Verapamil (Isoptin, etc.)

Comment:

Eplerenone is metabolized primarily by CYP3A4, and inhibitors of CYP3A4 may produce marked increases the serum levels of eplerenone. This may increase the risk of eplerenone toxicity, and the manufacturer states that eplerenone is contraindicated with potent CYP3A4 inhibitors. Aprepitant is a moderate inhibitor of CYP3A4, but is also likely to increase eplerenone concentrations.

Class 2: Use Only if Benefit Felt to Outweigh Risk

• Use Alternative: Use an alternative to the enzyme inhibitor if possible.
• Calcium channel blockers: Calcium channel blockers other than diltiazem and verapamil are unlikely to inhibit CYP3A4.
• Grapefruit: Orange juice does not appear to inhibit CYP3A4.
• Monitor: If CYP3A4 inhibitors are used with eplerenone, monitor for excessive eplerenone effects such as hypotension and hyperkalemia; reduce eplerenone dose as needed.