Vasodilator and Hypertensive Emergency

d XIV. Vasodilator * From the Latin words "vasa," which means "vessel," and "dilate," which means "to make wider.“ * Work by relaxing the smooth muscles that line the walls of blood vessels -- causing the blood vessels to increase in diameter and allow blood to flow through more easily. * Vasodilators also increases plasma rennin concentration resulting in sodium and water retention but these undesirable side effects can be blocked by concominant use of a diuretic and a beta blocker. * Vasodilators aren't a cure for high blood pressure; however, they can help control the condition.

a. HYDRALAZINE * Causes direct vasodilation , acting primarily on arteries and arterioles which results in decreased peripheral resistance * Usually taken with beta blocker propanolol to balance reflex tachycardia and diuretic to decrease sodium retention. * Onset of action: 10-20 minutes * Duration of action: 12 hours
INDICATION:
* Treat moderate to severe hypertension

VASODILATION: * Opens k+ channels and relaxes the smooth muscles of arterioles. * This leads to decrease in peripheral vascular resistances. * Decrease in arterial blood pressure.
ADVERSE EFFECTS OF HYDRALAZINE * CNS: * * Headache * Dizziness * Peripheral neuropathy * CVS: * Palpitation * Reflex tachycardia * Angina * arrhythmias
GIT:
* Nausea.
SKIN:
* Sweating * Lupus-like-syndrome can occur with high dosage but reversible if discontinued use B. MINODIXIL * a type of vasodilator. It relaxes blood vessels, increasing the blood and oxygen supply to your heart. This medicine is used to treat high blood pressure. * causes dilation of arterioles but not of venules. * Reflex tachycardia and fluid retention may be severe and require concomitant use of loop diuretic and b-blocker. * Causes serious sodium and water