Vasodilators and management of hypertensive emergencies

Author Department

Medicine; Pharmacy

Document Type

Book Chapter

Publication Date



Hypertensive emergency is an important clinical entity, which may result in end-organ damage involving neurological, cardiovascular, and renal systems. If not recognized and acted upon promptly, it can result in life-threatening adverse outcomes. Vasodilators form the mainstay of treatment in hypertensive emergencies. There are different classes of vasodilators based on the site and mechanism of action. The most commonly used vasodilators include directly acting drugs that act via the vascular nitric oxide pathway, calcium channel blockers, beta blockers, alpha blockers, and peripheral dopamine agonists. The various classes of vasodilators act via different neurohormonal signaling pathways and reduce the blood pressure by decreasing the peripheral resistance. Despite the availability of several medications, there is still paucity of literature regarding the best antihypertensive medication to be employed as well as the ideal rate of decreasing the elevated blood pressure in a given clinical scenario. This chapter reviews the basic pharmacology and the mechanism of action of commonly used vasodilators. It also reviews the approach to choosing the most appropriate drug based on the target organ involvement in diverse clinical scenarios of hypertensive emergency.