TABLE 37.5 MOST COMMONLY USED ANTIHYPERTENSIVE AGENTS FOR THE TREATMENT OF HYPERTENSIVE URGENCIES AND EMERGENCIES IN CHILDREN a , b Sodium Nitroprusside Nitroprusside is a powerful vasodilator, affecting both arteriolar and venous smooth muscle Its onset is almost immediate, and its duration of action is extremely short, allowing for easy titration of the drug to the desired blood pressure Because of its venous dilatory effects, nitroprusside reduces preload and