Htn Cology Flashcards
What is the mechanism of action (MOA) of diuretics?
They deplete Na+ stores in the body, increasing water elimination.
Initial use reduces blood volume and cardiac output, leading to compensatory vasoconstriction and increased peripheral vascular resistance.
What are the primary uses of diuretics?
Used for mild or moderate hypertension, lowering blood pressure by 10-15 mmHg.
Often combined with sympatholytic and vasodilators to counteract sodium retention.
List the classes of diuretics.
- Loop diuretics
- Thiazide diuretics
- Potassium-sparing diuretics
What is the site of action for loop diuretics?
Thick ascending limb of the loop of Henle.
What is the mechanism of action (MOA) of loop diuretics?
They inhibit Na+, K+, 2Cl- symport.
Name two examples of loop diuretics.
- Furosemide
- Bumetanide
What are the adverse effects (A/E) of thiazide diuretics?
- Hypocalcemia
- Metabolic alkalosis
- Hyperglycemia
- Hyperlipidemia
- Hyperuricemia
What is a key contraindication for thiazide diuretics?
Contraindicated in gout due to hyperuricemia.
What is the use of potassium-sparing diuretics?
Used in combination with other diuretics to avoid excessive K+ loss.
What are the two types of potassium-sparing diuretics?
- Inhibitors of renal epithelial Na+ channels
- Aldosterone antagonists
What is the mechanism of action (MOA) of central acting sympatholytic drugs?
They stimulate presynaptic α2 receptors in the brain stem, leading to decreased norepinephrine release.
Name an example of a ganglionic blocker.
Trimetaphan camsylate.
What is the MOA of adrenergic neuron blockers?
They deplete stores of catecholamines and prevent normal release of norepinephrine.
What are the adverse effects of alpha blockers?
- Drowsiness
- Weakness
- Orthostatic hypotension
- Reflex tachycardia
What are the two types of beta blockers?
- Non-selective (β1 + β2) blockers
- Cardio-selective (β1) blockers
What is the effect of beta blockers on the heart?
They block β1 receptors, leading to decreased heart rate, myocardial contractility, and cardiac output.
What is the primary use of mixed α and β blockers?
Used for emergency treatment of hypertension.
What is the mechanism of action (MOA) of direct vasodilators?
They cause relaxation of smooth muscles leading to vasodilation.
List some examples of arterial vasodilators.
- Hydralazine
- Minoxidil
- Diazoxide
- Fenoldopam
What are the adverse effects of calcium channel blockers (CCBs)?
- Reflex tachycardia
- Peripheral edema
- Flushing
- Dizziness
- Headache
What are the two categories of calcium channel blockers?
- Non-dihydropyridines (e.g., Verapamil, Diltiazem)
- Dihydropyridines (e.g., Nifedipine, Amlodipine)
What is the mechanism of action (MOA) of RAAS inhibitors?
They inhibit the renin-angiotensin-aldosterone system, leading to decreased blood pressure.
What is an example of a direct renin inhibitor?
Aliskiren.
What are the common adverse effects of ACE inhibitors?
- Dry cough
- Angioedema
- Hyperkalemia
- Hypotension
What is a key difference between ACE inhibitors and ARBs?
ARBs block angiotensin II at AT1 receptors without affecting bradykinin.
What are the adverse effects of aldosterone antagonists?
- Hyperkalemia
- Gynecomastia (especially with spironolactone)
True or False: All RAAS inhibitors are contraindicated during pregnancy.
True.
