* 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.
* 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
* Treat moderate to severe hypertension
* 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
* Peripheral neuropathy
* Reflex tachycardia
* 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 retention leading to edema and congestive heart failure INDICATION
* Severe to malignant hypertension that is refractory to other drugs. * Can be applied topically for correction of baldness in males. VASODILATION:
1. Opens k+ channels in smooth muscles of arterioles.
2. Hyperpolarization of smooth muscles leading to dilation of blood vessels. 3. Decrease in peripheral vascular resistance.
4. Decrease in blood pressure.
* Pericardial effusion
* Hirsuitism (hypertrichosis) in
XV. HYPERTENSIVE EMERGENCY
* Parenteral drugs are used to lower blood pressure rapidly (within a few hours). * As soon as reasonable blood pressure is achieved, oral therapy should be substituted. * Hypertensive emergency means blood pressure is so high that organ damage can occur. Blood pressure must be reduced immediately to prevent imminent organ damage. This is done in an intensive care unit of a hospital. * End organ damage:
eyes: retinal hemmorhages, papilledema
brain: cerebral edema, hemmorhage, seizure, altered mental status heart: angina
kidney: proteinurea, hematurea
blood and vessels: aortic dissection, hemolytic anemia
Symptoms of a hypertensive emergency include:
* Headache or blurred vision
* Increasing confusion or level of consciousness
* Increasing chest pain
* Increasing shortness of breath
* Swelling or edema (fluid buildup in the tissues)
What's the Treatment for Hypertensive Emergency and Associated Organ Damage? * In a hypertensive emergency, the first goal is to bring down the blood pressure as quickly as possible with intravenous (IV) blood pressure medications to prevent further organ damage. Whatever organ damage that has occurred is...