antihypertensives Flashcards
when does hypertension occurs
when systolic blood pressure
exceeds 130 mm Hg or diastolic blood pressure exceeds 80mm Hg on at least two occasions.
what diseases results in hypertension
increased peripheral vsm tone
what are the complications of HTN
heart disease,strokes,HF,and chronic kidney disease
what are the HTN stages
normal—-<120 sys——<80 dia
elevated ——120-129 sys—–80-89 dai
stage 1 ———130-139 sys——–80-89 dia
stage 2——— >140 sys——->90 dia
what is the etiology of HTN
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More than 90% of patients have essential HTN.
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A family history of HTN increases the likelihood that an individual will develop HTN.
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Its prevalence increases with age
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Non-Hispanic blacks have a higher incidence of HTN than do both non-Hispanic whites and Hispanic whites .
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Persons with diabetes, obesity, or disability status are more likely to have HTN.
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Environmental factors, such as a stressful lifestyle, high dietary intake of Na+, & smoking, may further predispose an individual to HTN.
what is the MOA for controling bp
two main mechanisms: baroreflexes (sympathetic) and RAAS(renin-angiotensin-aldsterone system)
what are the goals of HTN treatment
reduce CV and renal morbidity and mortality
the systolic should be less tha 130 and diastolic less than 80
what should we think about when choosing the treatment for HNT
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If BP is inadequately controlled, a second drug should be added, with the selection based on minimizing the adverse effects if the combined regimen and achieving goal BP.
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Patients with systolic BP greater than 20 mm Hg above goal or diastolic BP more than 10 mm Hg above goal should be started on two antihypertensives simultaneously.
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Combination therapy with separate agents or a fixed-dose combination pill may lower BP more quickly with minimal adverse effects.
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A variety of combination formulations of the various pharmacologic classes are available to increase ease of patient adherence to treatment regimens that require multiple medications.
how do diuretics work for HTN
by reducing the blood volume therefore the BP
how does thiazide diuretics work?
hydrochlorothiazide and chlorthalidone lower bp by increasing NA and water excretion
they are the initial drug
they are useful with B blockers, ACEI , ARBS, Potassium-sparing diuretics
may cause hypokalemia, hyperuricemia, and
hyperglycemia.
why isnt metolazone useful as a thiazide diuretic in combinations
because its not effective with inadequate kidney function patients
how do loop diuretics work in HTN
The loop diuretics (furosemide, torsemide, bumetanide ðacrynic acid) act promptly by blocking Na and Cl
reabsorption in the kidneys, even in patients with poor renal function or who have not responded to thiazides diuretics.
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Rarely used in HTN, mostly for HF and edema
what are the uses of potassium sparing diuretics for HTN
Amiloride and triamterene (inhibitors of epithelial Na transport at the late distal and collecting ducts) as well as spironolactone and eplerenone (aldosterone antagonists) reduce potassium loss in the urine.
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Aldosterone antagonists have the additional benefit of
diminishing the cardiac remodeling that occurs in HF.
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Used in combination with diuretics to reduce K loss
what are the pharmacokinetics of Beta blockers
orally active
◼ Propranolol undergoes extensive and highly variable
first-pass metabolism.
◼ Oral β-blockers may take several weeks to develop
their full effects.
◼Esmolol, metoprolol, and propranolol are available
in intravenous formulations
what are the side effects of beta blockers
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Alterations in serum lipid patterns:noncardioselective β-blockers may disturb lipid metabolism, decreasing HDL cholesterol and increase triglycerides.
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Drug withdrawal: Abrupt withdrawal may
induce HTN, angina, MI, and even sudden
death in patients with IHD. Therefore, these
drugs must be tapered over a few weeks in
patients with HTN and IHD.