Pharmacology Flashcards
What is the mechanism of action of beta blockers?
- decrease cardiac output
- decrease PVR by decreasing renin release to lower angiotensin II LEVLES and blocking norepinephrine in CNS
- block RAAS- decrease caridac output and PVR
- some block alpah 1 receptors in vasculature to decrease PVR
Which medications are cardioselective beta blockers? which receptors do they block?
- atenolol
- metoprolol
These medications block B1 receptors
which beta blockers are vasodilating nonselective beta blockers? which receptors do they block?
- cavedilol
- Labetalol
These medications block A1, B1, B2
when should you use BP medications for secondary prevention?
recurrent CVD events in patients with clincial CVD and average BP >130/80mmHg
when should you use BP medications for primary prevention?
- patients with an estimated 10 year risk ASCVD > 10% and average BP > 130/80mmHg
- stage II hypertension
what are first line agents for hypertension?
thiazide diuretics, calcium channel blockers (dihydropyridine) and ace inhibitors or ARBs
Which medications are RAAS inhibitors?
ACEi, ARBs, DRI
In black adults with HTN but without HF or CKD, including those with DM, initial treatment should include?
Thiazide-type diuretic or CCB
Women with hypertension who become pregnant should avoid?
ACEi, ARBS, ARNI or direct renin inhibitors
What is the mechanism of action of ACE inhibitors?
Decrease production of angiotensin II and decrease the release of aldosterone
what is the mechanism of action of ARBs?
Competitive antagonism of angiotensin II receptors
what is the mechanism of action of direct renin inhibitors?
block release of renin form juxtoglomerular cells
which medication are Ace inhibitors
- captopril
- enalapril
- lisinopril
which medications are ARBs?
Losartan
valsartan
candesartan
in which patients are ACEi beneficial? what are there contraindications?
- beneficial in patients with MI, HF, CKD, DM, proteinuria
- contraindications: bilateral renal stenosis, pregnancy, history of angioedema (ARBs have same contraindication)
avoid combining with other RAAS inhibitors, potassium sparing diuretics
avoid using with potassium supplements or salt substitutes
what are some side effects of ACEi
- hypotension
- renal dysfunction
- hyperkalemia
- cough
- angioedema
- taste changes
avoid in pts with symptomatic hypotension, or salt-depletion
- effective as monotherapy, most commonly used as second agent in combo wiht thiazide
- do not use with other RAAS inhibitors or with drugs that increase risk for hyperkalemia
- same contraindications (pregnancy, BRS) and drug interactions as ACE, ARBs
- side effects: hypotension, hyperkalemia, diarrhea, abdominal pain, low risk of angioedema and cough
DRI (aliskerin)
which medications are thiazides? thiazide like? potassium sparing?
- thiazides: hydrochlorothiazide, chlorothiazide
- thiazide like: chlorthalidone, indapamide
- potassium sparing: amiloride, triamterene
mechanism of action of diuretics?
- initally decrease preload and cardiac output
- decrease PVR (MOA is unknown)
- increasing dose does not increase BP lowering effect
- Avoid in renal dysfunction
- contraindication: anuric patients, sulfa allergy, gout
- side effects: hypotension, mild metabolic acidosis, hyperlipidemia, hyperuricemia, impotence
- use cautiously with NSAIDS, digoxin, lithium, antidiabetic meds
- monitor BUN/Scr and potassium levels after initiation
- prevent hypokalemia
thiazide
- least potent diuretic
- slight (amiloride) to no (triamterene) antihypertensive effecs
- avoid in severe renal dysfuntion
- contraindications: anuric, hyperkalemia
Potassium sparing diuretics
What is the mechanism of action of calcium channel blockers?
- decrease PVR
- decrease cardiac output by decreasing heart rate and contractility
Can cause reflex tacchycardia and peripheral edema
which medications are dihydropyridine calcium channel blockers?
- Nifedipine
- amlodipine
which medications are non-dihydropyridine calcium channel blockers
Verapamil
diltiazem
decrease PVR, decrease HR
have negative inotropic and chronotropic effects
What are some side effects of calcium channel blockers?
- hypotension, HA, flushing, constipation, peripheral edema, angina, worsening HF sysmptoms (non-DHP), gingival hyperplasion (DHP)
- Vasodilating lower BP more than other in this class
- add to first line therapy for these indications
- selection shoud be based on liver and/or renal function, co-morbid conditions, and need for cardioselectivity
- side effects: hypotension, bradycardia, AV block fatigue, masks signs of hypoglycemia, hyperlipidemia, impotence, SOB, feeling cold
- must taper over 1-2 weeks rather than D/C abruptly
Beta blocker
contraindication: Asthma/COPD, high degree AV block, sick sinus syndrome
- receptors located in vascular smooth muscle, urethra, prostate, and bladder sphincter
- MOA: selectively block post-synaptic receptors to cause peripheral vasodilation of ateries and veins
- potent vasodilators so can cause tacchycardia and RAAS
- side effects: first dose phenomenon, orthostatic hypotension, syncope, peripheral edema, nasal congestion
- start low, taper slowing, administer 1st dose at bedtime
alpha blockers
which medications are alpha blockers?
- doxazosin
- prazosin
- terazosin
- mixed group of drugs that work in the CNS to inhibit SNS (norepinephrine activity)
Central acting agents
Methyldopa, clonidine
MOA: converted to alpha-methyl norepinephrine, a false neurotransmitter that stimulates central alpha-2 receptors to reduce sympathetic outflow from CNS (little effect on CO)
methyldopa
MOA: reduce sympathetic tone within brainstem by stimulating alpha-2 receptors to inhibit outflow of impulses (slight effect on CO)
Clonidine
- use as third-fourth line agents due to side effects- combine with a diuretic to minimize edema
- most useful in patients with hard to control BP and during hypertensive urgencies
- side effects- bradycardia, hypotension, dizziness, orthostatic hypotension, edema, sedation, dry mouth, constipation, impotence
- one med has withdrawal or rebound hypertension due to short half life (taper)
central agents
(clonidine, methyldopa)
taper clonidine. methyldopa can cause drug induce hepatitis
Group of drugs that directly vasodilate arteries, rather than inhibiting a vasoconstricting mediator or blocking a receptor channel
hydrazaline: relaxes vascular smooth muscle possibly by increasing the concentration of nitric oxide
minoxidil: opens potassium channels in vascular smooth muscle
direct vasodilator
use in combo with BB to minimize reflex tach. and loop to minimize edema
- indication: resistant HTN due to primary aldosteronism
- bp lowering benefit also seen in patients with normal aldosterone
- other indications: obesity related HTN, high sodium diet
- Spironolactone (nonselective) and eplernone (selective)
- MOA: decrease cardiac output and decrease preload
- contraindications: CKD
- side effects: hyperkalemia, dizziness, hypotension, (spirogynecomastia, breast tenderness, hisutism, mestrual changes)
Aldosterone antogonist
which medications are aldosterone antagonists?
spironolactone, epelernone
which medications are direct vasodilators?
hydralazine
minoxidil
