Table 3.

Drug interactions between antiretrovirals and commonly used antihypertensive therapy.

Antihypertensive Class	Specific Classes/Agents	Drug Interactions	Notes
Diuretics [194]	thiazides, thiazide-like, loop, potassium-sparing	Unlikely to occur	Metabolized outside CYP450
β-blockers [195-201]	Hepatically metabolized: propranolol, metoprolol	PIs, EFV	Increased concentrations of β-blockers: prolong effect, increase risk of adverse effects
	Hydophilic: nadolol, atenolol	Not thought to exist	Excreted in the urine
Calcium channel blockers (CCB) [202-204]	Verapamil, diltiazem, amlodipine, nifedipine	PIs, NNRTIs	PIs: increased concentrations of CCB, prolonged effect NNRTIs: reduced bioavailability of CCB
Angiotensin-converting enzyme inhibitors [205-208]		Not expected to occur	Metabolized outside CYP450
Angiotensin II receptor blockers [209-216]	Losartan	CYP2C9 inhibitors, PIs	CYP2C9 inhibitors: Decreased losartan efficacy PIs: increased losartan serum concentrations
	Candesartan, irbesartan	Not thought to exist	Undergo hepatic metabolism, do not require biotransformation
	Eprosartan, olmesartan, telmisartan, valsartan	Not thought to exist	Metabolized outside CYP450

PIs protease inhibitors, EFV efavirenz, NNRTIs non-nucleoside reverse transcriptase inhibitors, CCB calcium channel blockers.