Angiotensin Ii Receptor Blockers: an Overview

Blockage of the renin-angiotensin system (RAS) is now recognized as an effective approach to the treatment of hypertension and congestive heart failure. Today, it is possible to antagonize the effects of angiotensin II (AT-II) more specifically by blocking its receptors by using nonpeptide receptor antagonists. AT-II-receptor antagonists were developed as agents that would more completely block the RAS and thus decrease the adverse effects seen with Angiotensin Converting Enzyme (ACE inhibitors). AT-II-receptor antagonists include losartan, valsartan, irbesartan, candesartan, eprosartan and telmisartan. The adverse effects of AT-II-receptor antagonists dizziness, headache, upper-respiratorytract infection, cough, and gastrointestinal disturbances occur at about the same rate as with placebo. Four of them have recently been launched on the market and several others are preregistered for the treatment of hypertension. These new molecules are as effective as ACE inhibitors, calcium antagonists and beta-blockers in lowering blood pressure in hypertensive patients. When compared to ACE inhibitors, they appear to have comparable favorable effects on systemic and renal hemodynamic properties. All available AT-II-receptor antagonists seem to be equally effective in reducing both systolic and diastolic blood pressure. Currently, AT-II-receptor antagonists are used either as monotherapy in patients who cannot tolerate ACE inhibitors or in combination with other antihypertensive agents. In this review we summarize the combined therapy of ACE inhibitors and AT-II receptor antagonists play in ischemic heart disease. In this respect the review will improve ideas for developing new formulations with combinations of these drugs in the future.