HTN3 Flashcards
what are the 3 major groups of antiHTN agents
- volume depleters
- adrenergic inhibitors
- vasodilators
what antiHTN agents are considered vasodilators?
ACEI
CCB
ARB
what antiHTN agents are considered volume depleters?
diuretics
what is the MOA of thiazides on HTN initially
Initially:
decrease extracellular fluid volume
decrease cardiac output and BP
increase systemic vascular resistance (SVR)
what is the MOA of thiazides on HTN chronically
decrease systemic vascular resistance due to compensation
list the thiazide diuretics
- hydrocholorothiazide
- indapamide
- metolazone
- chlorthalidone
- indapamide
why are thiazides preferred in combo therapy
synergistic affect by blocking compensatory fluid (and Na) retention mechanisms
what patients should not be given thiazide diuretics for HTN?
why
patients with renal failure (CrCl < 30)
thiazides compete with endogenous organic acids that build up in renal insufficiency
what effect does thiazide have on arteriolar walls
mobilize sodium and Na from arteriolar walls, reducing pressure on lumen
what effect do thiazide diuretics have on the lumen of a vessel?
What can blunt this effect?
lumen relaxes and diameter increases
high dietary sodium
what electrolytes may be adversely increased due to thiazides
increased calcium
increased uric acid
increased glucose
what electrolytes may be adversely decreased due to thiazides
decreased potassium
decreased sodium
decreased magnesium
what type of drugs most commonly cause electrolyte imbalances
Thiazides
patients with gout should avoid what class of drugs? why?
thiazides
increases uric acid levels, people w/ gout should never take thiazides
what drugs can be used to counterbalance thiazides effects on potassium
ACEI cause hyperkalemia
thiazides cause hypokalemia
