Drug class	Drugs potentially affected by grapefruit	Effects of interaction	Alternative treatments
Antiarrhythmics	Amiodarone (Cordarone), disopyramide (Norpace), quinidine	Increased plasma concentrations of amiodarone may cause thyroid or pulmonary toxicity, liver injury, QTc prolongation, proarrhythmic disorders, and bradycardia.¹⁹	Digoxin (Lanoxin), diltiazem (Cardizem), verapamil (Calan) Beta blockers
Antiarrhythmics	Amiodarone (Cordarone), disopyramide (Norpace), quinidine	Increased plasma concentration of quinidine and disopyramide may be cardiotoxic causing torsades de pointes.^9,20
Calcium channel blockers	Felodipine (Plendil), nicardipine (Cardene), nifedipine (Procardia), nimodipine (Nimotop), nisoldipine (Sular)	Increased plasma concentration may lead to flushing, peripheral edema, headaches, tachycardia, symptomatic hypotension, and myocardial infarction in rare cases.⁹	Amlodipine (Norvasc), diltiazem (Cardizem), verapamil (Calan)
Statins	Atorvastatin (Lipitor), lovastatin (Mevacor), simvastatin (Zocor)	Increased plasma concentration may cause headaches, gastrointestinal complaints, hepatic inflammation, and myopathies (e.g., rhabdomyolysis).^21–24	Fluvastatin (Lescol), pravastatin (Pravachol), rosuvastatin (Crestor) Fibric acids, nicotinic acid, or bile acid sequestrants
Immunosuppressants	Cyclosporine (Sandimmune, Neoral), tacrolimus (Prograf)	Increased drug exposure without effects on peak concentration may cause increased adverse events or toxicity evidenced by renal toxicity, hepatic toxicity, and increased immunosuppression.^25–29	No alternatives available
Protease inhibitors	Saquinavir (Fortovase)	Increased plasma concentrations may cause increased side effects such as headache, fatigue, insomnia, and anxiety.³⁰	Amprenavir (Agenerase), atazanavir (Reyataz), fosamprenavir (Lexiva), indinavir (Crixivan), lopinavir/ritonavir (Kaletra), nelfinavir (Viracept), ritonavir (Norvir)