Antihypertensives Flashcards
Antihypertensive drug classes (list 6)
diuretics, inhibitors of RAS (ACEi, ARB, renin inhibitor), CCB, sympatholytics (alpha-1/beta antagonists), vasodilators, CNS agents
Spironolactone site of action
blocks aldosterone receptor
CCB subclasses & differences between subclasses
DHP and non-DHP; DHP effect on vasculature (arteries > veins), non-DHP effect on heart and vasculature
What does bradykinin do?
Vasodilates, also causes cough
Diuretic classes
thiazide, loop diuretic, K+ sparing, osmotic
DHP example, MOA/result
Amlodipine (-ipine); acts on VASCULATURE (little heart action), vasodilates
ACEi example, MOA, main effect
ramipril; inhibit ACE» inhibit vasocontriction, aldosterone secretion, and NaCl reabs, and incr vasodilation (BK); result: decr SVR (dual effect), naturesis/diuresis
2 things ACE does in RAS
convert Angiotensin I to II, inactivate Bradykinin (NB bradykinin causes cough)
Beta blocker example, MOA/result
Propranolol (-lol); act on beta-1 receptors; decr HR &contractility, decr renin secretion, decr SNS activity
Spaces in RAS that can be blocked
Beta-1 receptor (no renin), renin (no Angiotensinongen»_space; AI), ACE (no AI»_space; AII, no BK inactivation), AT1 (no AII effect)
Most powerful diuretic
loop diuretics (furosemide)
non-DHP example, MOA/result
Verapamil and Diltiazem; activity on heart and vasculature, reduce HR & contractility, vasodilates
ARB example, MOA, result
Losartan (-sartan); more downstream so no effect on bradykinin (less cough, angioedema, and vasodilation); no vasoconstriction & Na retention
CCB (DHP & non-DHP) adverse effects
DHP: reflex tachycardia, prefer slow-onset long acting agents; non-DHP: cardiodepressant effects, watch out for pt w/ HF or on beta blocker
How many ACEi delay diabetic nephropathy?
AII constricts efferent glomerular vasculature; will relax efferent and lessen pressure on glomerulus
What does Angiotensin II do?
Act on AT1; vasoconstrict, NaCl reabsorption, more aldosterone
Beta blocker types and examples
cardioselective (metoprolol, beta-1), non-cardioselective (propranolol, beta-1/2; carvedilol, alpha1/beta1/2), partial agonist (acebutolol, partial beta-1 agonist)
Beta-blocker adverse effects
bronchoconstriction (if beta-2 blocked, non-cardioselective contra in asthma), fatigue
ACEi adverse effects
cough, angioedema (swollen tongue, throat, lips; serious), hyperkalemia (decr aldosterone, can’t reabs Na+ by excreting K+), renal dysfunction (no AII to maintain GFR)
What does aldosterone do?
Act on aldosterone receptor for Na+ retention
Loop diuretic eg
Furosemide
Diuretic MOA
naturesis and diuresis, NB antihypertensive efficacy not proportional to diuretic effect (thiazide very effective but not strong)
ALLHAT study. What is it? What did it show?
looked at mortality, CV and safety of drugs; a-1 antagonist withdrawn; equal deaths & coronary heart disease, thiazide less stroke, thiazide & ACEi less HF, thiazide & CCB less withdrawal
CNS agents (alpha-2 agonist) example, MOA, effect
Chlonidine; feedback inhibition of NE release; decr HR, SV & SVR; DANGEROUS drug, rarely used
