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Flashcards in Drugs that affect the Vasculature Deck (17):
1

What classes of drugs act on the vasculature? (there are more but this lecture focuses on 2 main types)

Vasodilators

Anti-adrenergic

2

What are the 4 direct acting vasodilators?

Hydralazine

Minoxidil

Sodium nitroprusside

Fenoldopam

3

Hydralazine

Direct acting vasodilator- arteriole vasodilator

Htn, heart failure (+nitrate)

Decreases resistance to LV doesnt need to pump as hard --> increases CO

Low bioavailability, short half life

SE: HA, palpitations, flushing, nausea, anorexia, lupus like syndrome

4

Minoxidil

Direct vasodilator: arteriolar (increased K channel permeability)

Severe or refractor htn (rarely used!)

SE: reflex tachycardia, fluid retention, hypertrichosis (excessive hair growth--ROGAINE), pericardial effusion

5

Sodium nitroprusside

"balanced" vasodilator- acts on arteries and veins; potent/rapid

metabolized to NO and to cyanide

Decrease arterial/systemic resistance, increase venous capacitance -- works best on pt with normal or reduced LV function

Treat hypertensive emergency (with beta blocker) & severe CHF -- IV infusion, 30 seconds to on, minutes off

SE: thiocyanate toxicity --> blurred vision, tinnitus, disorientation, nasuea

6

Fenoldopam

Direct acting vasodilator-- arteriolar

dopamine 1 agonist --> vasodilation

Thought to enhance renal perfusion 

IV, rapid onset, rapid offset, metabolized in liver, renally excreted

SE: HA, dizzy, tachycardia, increased intraocular pressure (avoid in pt with glaucoma)

7

Nitrates

What conditions? Mechanism? Contraindications? How administered?

Vascular smooth muscle relaxation --> venodilation --> CO falls secondary to this

Use for angina, acute coronary syndromes, HF

Don't use in preload sensitive patients i.e. RV MI

Fast acting formulas for acute i.e. sublingual

Chronic i.e. oral, transdermal

IV nitroglycerin for unstable angina, pulm edema, HF

Drug tolerance develops with continued use- drug holiday

SE: hypotension, reflex tachycardia, HA, flushing

8

What is the main 5-phosphodiesterase-5 inhibitor?

Sildenafil

9

Sildenafil

PhDiEs-5 inhibitor --> decreases pulm vasc resistance in pt with pulm arterial htn

Don't use with nitrates or viagra!! Severe systemic hypotension

10

Calcium Channel blockers: how they work and 2 main classes

Decreases intracellular Ca concentrations --> vasodilation in vasc smooth muscles and/or inotropic effect in cardiac cells

Non-dihydropyridines: mainly negative inotrope
-Verapamil
-Diltiazem

Dihydropyridines: mostly vasodilators
"-ipine"

11

When do you use Ca Channel blockers?

2nd line for angina

Coronary artery spasm

Htn

Verapamil and Dilitazem: Supraventricular Arrhythmias

12

What are the SE of Ca Channel blockers?

Verapamil: hypotension, bradycardia, AV block, constipation

Diltiazem: hypotension, peripheral edema, bradycardia

Dihydropyridines: hypotension, HA, flushing, peripheral edema (esp amlodipine)

13

What are the 4 main anti-adrenergic classes?

CNS alpha 2 agonists

Beta blockers

Peripheral alpha antagonists

Reseripine: sym nerve ending antagonist

14

Alpha and beta receptors location/response

A image thumb
15

What are the CNS alpha 2-antagonists? What is their effect?

Diminished sympathetic outflow from the medulla --> decreased peripheral vasc resistance, drop in BP and HR

Clonidine, alpha-methyldopa, guanabenz, guanfacine

SE: refractory htn

16

Reseripine

Symp nerve-ending antagonist

Inhibits NE uptake --> depletion of catecholamines --> decreased TPR

SE: CNS toxicity (sedation, loss of conc, psychotic depression) = rarely used! Reserpine is the serpent for your brain

17

What are the main peripheral alpha antagonists?

Alpha-1 selective: "-sin": prazosin, terazosin, doxazosin (CHF risk)
** these are great for benign, prostatic hypertrophy; also used for htn but not as much

Non-selective: phentolamine, phenoxybenzamine
*** great for pheochromocytoma