Drinking grapefruit juice (or eating the fruit) with these drugs may lead to higher-than-expected levels of medication in your body. Avoid complications by taking the following pills with water:

Amiodarone (Cordarone), a drug used to treat arrhythmias
Buspirone (BuSpar), clomipramine (Anafranil), or sertraline (Zoloft), antidepressants
Carbamazepine (Carbatrol, Tegretol), anti-seizure medications
Cyclosporine (Neoral, Sandimmune), tacrolimus (Prograf), or sirolimus (Rapamune), immunosuppressant drugs
Diazepam (Valium), or triazolam (Halcion), tranquilizers
Felodipine (Plendil), nifedipine (Adalat, Procardia), nimodipine (Nimotop), nisoldipine (Sular), and potentially verapamil (Isoptin, Verelan), high blood pressure medications
Methadone, a pain reliever
Saquinavir (Invirase), or indinavir (Crixivan), HIV medications
Sildenafil (Viagra), an erectile dysfunction medication
Simvastatin (Zocor), lovastatin (Mevacor, Altoprev), atorvastatin (Lipitor), or simvastatin-ezetimibe (Vytorin), cholesterol-lowering medications

Source: The Mayo Clinic

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