Drug	Black box warnings*	Adverse effects	Medications to avoid†	Food requirements	Miscellaneous
Amprenavir (Agenerase)7	Because of potential risk for toxicity from substantial amounts of the excipient propylene glycol, the oral solution is contraindicated in pregnant women, children younger than 4 years, patients with hepatic or renal failure, and patients treated with disulfiram (Antabuse) or metronidazole (Flagyl). The oral solution should be used only when capsules or other PIs cannot be used.	Gastrointestinal intolerance, rash, oral paresthesias, transaminase elevation, hyperglycemia, fat redistribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Bepridil (Vascor), dihydroergotamine mesylate (DHE 45), ergotamine (Ergostat), lovastatin (Mevacor), midazolam (Versed), rifampin (Rifadin), simvastatin (Zocor), triazolam (Halcion), St. John's wort, garlic supplements	Can be taken with or without food but not with high-fat meals (fat decreases blood concentration).	Store at room temperature. May increase levels of sildenafil (Viagra); do not exceed 25 mg in a 48-hour period.
Atazanavir (Reyataz)9	None	Nausea, jaundice, arrhythmia, hyperglycemia, fat redistribution. May increase bleeding episodes in patients with hemophilia.	Bepridil, cisapride (Propulsid), ergotamine, indinavir (Crixivan), lovastatin, midazolam, pimozide (Orap), rifampin, simvastatin, triazolam, St. John's wort, garlic supplements	Take with food.	Store at room temperature.
Enfuvirtide (Fuzeon)10,11	None	Injection site reactions, hypersensitivity reactions, eosinophilia.	None	None (injection)	None
		In clinical trials, rate of bacterial pneumonia increased in treated patients.
Indinavir (Crixivan)7	None	Nephrolithiasis, gastrointestinal intolerance and nausea, increased indirect bilirubinemia, transaminase elevation, headache, asthenia, blurred vision, dizziness, rash, metallic taste, thrombocytopenia, alopecia, hyperglycemia, hemolytic anemia, fat redistribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Dihydroergotamine mesylate, ergotamine, lovastatin, midazolam, rifampin, simvastatin, triazolam, St. John's wort, garlic supplements	Take 1 hour before or 2 hours after meals. Can take with skim milk or a low-fat meal. Recommended water intake is at least 1.4 L (48 fl oz) per day.	Store at room temperature. Carbamazepine (Tegretol) substantially decreases blood levels; consider alternative agent. Grapefruit juice decreases blood levels by 26%. Increases levels of sildenafil by 340%; do not exceed 25 mg in a 48-hour period.
Lopinavir/ritonavir (Kaletra)7	None	Gastrointestinal intolerance, asthenia, elevated transaminase enzymes, hyperglycemia, fat redistribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Dihydroergotamine mesylate, ergotamine, flecainide (Tambocor), lovastatin, pimozide, propafenone (Rythmol), rifampin, simvastatin, triazolam, St. John's wort, garlic supplements	Take with food; a moderate-fat meal increases blood concentration of capsules and solution by 48% and 80%, respectively. Recommended water intake is 2 to 3 L (68 to 101 fl oz) per day.	Oral solution contains 42% alcohol. Refrigerated capsules are stable until expiration date; capsules can be stored at room temperature for 2 months. Decreases levels of ethinyl estradiol by 42%; use alternate method of contraception. May increase levels of sildenafil; do not exceed 25 mg in a 48-hour period.
Nelfinavir (Viracept)7	None	Diarrhea, hyperglycemia, transaminase elevation, fat redistribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Dihydroergotamine mesylate, ergotamine, lovastatin, midazolam, rifampin, simvastatin, triazolam, St. John's wort, garlic supplements	Take with a meal or snack.	Store at room temperature. Decreases norethindrone (Norlutin) levels by 18% and ethinyl estradiol levels by 47%; use alternate method of contraception. Increases atorvastatin (Lipitor) levels by 74%; use with caution. May increase sildenafil levels; do not exceed 25 mg in a 48-hour period.
Ritonavir (Norvir)7	Coadministration with certain nonsedating antihistamines, sedative hypnotics, antiarrhythmics, or ergot alkaloid preparations can result in potentially serious or life-threatening adverse events.	Gastrointestinal intolerance, paresthesias (circumoral and extremities), hepatitis, pancreatitis, asthenia, taste perversion, > 200% increase in triglyceride level, elevated creatine kinase and uric acid levels, hyperglycemia, fat distribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Amiodarone (Cordarone), bepridil, dihydroergotamine mesylate, ergotamine, flecainide, lovastatin, midazolam, pimozide, propafenone, quinidine, simvastatin, triazolam, St. John's wort, garlic supplements	Take with food, if possible, to improve tolerability.	Refrigerate capsules; capsules can be stored at room temperature for up to 30 days. Oral solution should not be refrigerated. Increases clarithromycin (Biaxin) levels by 77%. Adjust dosage in patients with renal insufficiency. Decreases ethinyl estradiol levels by 40%; use alternate method of contraception. Carbamazepine toxicity has been reported after introduction; use with caution and monitor anticonvulsant level closely. Increases desipramine (Norpramin) level by 145%; reduce dosage. Decreases theophylline level by 47%; monitor level. Doubles sildenafil level; do not exceed 25 mg in a 48-hour period.
Saquinavir (Fortovase)7	None	Gastrointestinal intolerance, dyspepsia, headache, elevated transaminase level, hyperglycemia, fat redistribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Dihydroergotamine mesylate, ergotamine, lovastatin, midazolam, rifampin, simvastatin, triazolam, St. John's wort, garlic supplements	Take with a large meal.	Refrigerate or store at room temperature for up to 3 months.
Saquinavir mesylate (Invirase)7	Saquinavir and saquinavir mesylate are not bioequivalent and cannot be used interchangeably.	Gastrointestinal intolerance, headache, elevated transaminase level, hyperglycemia, fat redistribution, and lipid abnormalities. May increase bleeding episodes in patients with hemophilia.	Dihydroergotamine mesylate, ergotamine, lovastatin, midazolam, rifampin, simvastatin, triazolam, St. John's wort, garlic supplements	When taken with ritonavir, timing of meals has no effect.	Store at room temperature. Grapefruit juice increases blood level. Increases sildenafil level 2- to 11-fold; use a 25-mg starter dose of sildenafil.