What is the primary purpose of losartan?

Losartan is primarily used as an angiotensin II receptor blocker (ARB). It works by blocking the effects of angiotensin II, a peptide that causes blood vessels to constrict. When these receptors are blocked, the result is vasodilation, which lowers blood pressure and allows for improved blood flow. This action is particularly beneficial in treating conditions such as hypertension (high blood pressure) and heart failure, as it helps to reduce the workload on the heart.

In contrast, calcium channel blockers primarily focus on inhibiting calcium ions from entering vascular smooth muscle and cardiac muscle, which is not the primary action of losartan. Additionally, while relaxing smooth muscles of blood vessels is a secondary effect of losartan due to its role in blocking angiotensin II, it is not the primary mechanism of action in comparison to its direct receptor blocking capability. Increasing blood flow to the heart is not a direct effect of losartan either, as its primary focus is on vascular resistance and blood pressure regulation rather than direct enhancement of coronary blood flow.