ANTIHYPERTENSIVE DRUGS

midterms

hypertension

is defined as either a sustained systolic blood pressure of greater than 140 mm Hg or a sustained diastolic blood pressure of greater than 90 mm Hg

15 - 30 mins

if engaging in physical activity, how long should you rest before taking your blood pressure

30 mins before meal

1-2 hrs meal after meal

if you just finished eating, how long should you rest before taking your blood pressure

hypertension

results from increased peripheral vascular arteriolar smooth muscle tone, which leads to increased arteriolar resistance and reduced capacitance of the venous system

• heart disease

• stroke

although many patients have no symptoms, chronic hypertension can lead to ___ and ___, the top two causes of death in the world

hypertension

is also an important risk factor in the development of chronic kidney disease and heart failure. the incidence of morbidity and mortality significantly decreases when this is diagnosed and is properly treated

cardiac output (CO)

volume of blood pumped by the heart per minute

peripheral resistance (PR)

resistance that blood encounters as it flows through the peripheral blood vessels of the body

CO X PR

BP =

BP - no change

↑ CO x ↓ PR = what bp

BP - elevated

CO - no change x ↑ PR = what bp

increased BP

↑ heart rate (↑ CO) x systemic vasoconstriction (↑ PR) = what bp

decreased bp

↓ stroke volume (↓ CO) x systemic vasodilation (↓ PR) = what bp

vasodilation = decrease PR = decrease BP

arteriolar tone (becomes vasodilated) = ____ PR = _____ BP

increased cardiac output = increase BP

increase heart rate, increase contractility, increase filling pressure (due to increased blood volume and venous tone) results to

increase peripheral resistance = increase BP

increase arteriolar tone results to

1. essential (aka. primary)

2. secondary

types of hypertension

essential hypertension (aka. primary)

• hypertension with no identifiable cause

• thought to be linked to genetics, poor diet, lack of exercise and obesity

true

a family history of hypertension increases the likelihood that an individual will develop hypertension

TRUE OR FALSE

true

the prevalence of hypertension increases with age, but decreases with education and income level

TRUE OR FALSE

TRUE

non-Hispanic blacks (Africans) have a higher incidence of hypertension than do both non-Hispanic whites (Caucasians, western Europe, great Britain) and Hispanic whites (Spanish, Portuguese)

TRUE OR FALSE

true

environmental factors, such as stressful lifestyle, high dietary intake of sodium, and smoking, may further predispose an individual to hypertension

TRUE OR FALSE

secondary hypertension

• hypertension caused by another medical condition

• caused by conditions that affect your kidneys, arteries, heart or endocrine system

blood pressure

the pressure with which the blood flows in the blood vessels is called

arteries

this blood vessel receive blood from the heart that’s why the pressure is high in this. blood pressure gradually decreases as blood flows into capillaries

veins

when blood is collected in this blood vessel, blood pressure is greatly reduced. so blood pressure is less here compared to the arteries

sphygmomanometer

instrument that measures blood pressure

in a sphygmomanometer, the numerator represents the SYSTOLIC PRESSURE while the denominator represents the DIASTOLIC PRESSURE

in a sphygmomanometer, the numerator represents the ___ while the denominator represents the ____

systole

refers to the period when your heart contracts and pushes blood out to the rest of your body

systolic blood pressure

this is measured when the ventricles are at its peak contraction, pumping blood out of the heart

diastole

is when the heart relaxes and refills with blood

diastolic blood pressure

this is measured when the blood returns to the heart. the left and right atrium opens, and ventricles relaxes

• blocking of arteries by cholesterol

• constant stress and strain

• improper functioning of kidneys

• smoking and alcohol consumption

reasons for hypertension

• diet control

• moderate exercise

• avoiding stress, smoking, and alcohol consumption

• taking appropriate medications

ways to prevent or treat hypertension

1. baroreceptors and the sympathetic nervous system

2. renin-angiotensin-aldosterone system (RAAS)

mechanisms of controlling blood pressure

baroreceptors

are specialized sensory nerve endings that detect changes in blood pressure, are primarily located in the walls of blood vessels. Specifically, they are found in the aorta (especially the aortic arch) and the carotid sinuses (the expanded portions of the carotid arteries in the neck)

baroreceptors

are a type of mechanoreceptors allowing for relaying information derived from blood pressure within the autonomic nervous system. Information is then passed in rapid sequence to alter the total peripheral resistance and cardiac output, maintaining blood pressure within a preset, normalized range

baroreceptors

receptor that detects low blood pressure and send messages to the brain to increase BP through sympathetic nervous system effect

baroreflex

is a crucial mechanism that helps regulate blood pressure and maintain homeostasis

renin-angiotensin-aldosterone system (RAAS)

• is a hormone system that regulates blood pressure and fluid balance

• plays a critical role in maintaining blood volume and electrolyte balance

• is a complex cascade of hormones and enzymes that work together to control blood pressure and fluid volume in the body

true

mild hypertension can sometimes be controlled with monotherapy, but most patients require more than one drug to achieve blood pressure control

TRUE OR FALSE

• thiazide diuretic

• ACE inhibitor

• angiotensin receptor blocker (ARB)

• calcium channel blocker

current recommendations to initiate hypertension therapy include

true

if blood pressure is inadequately controlled, a second drug should be added, with the selection based on minimizing the adverse effects of the combined regimen and achieving goal blood pressure

TRUE OR FALSE

• normal

• prehypertension

• stage 1 hypertension

• stage 2 hypertension

BP classification based on JNC 7 (Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure)

normal

BP classification

< 120 / 80

prehypertension

BP classification

120-139 / 80-89

stage 1 hypertension

BP classification

140-159 / 90-99

stage 2 hypertension

BP classification

≥ 160 / 100

hypertensive crisis (e.g., 180/100)

thiamine containing food combined with monoamine oxidase inhibitor results to

< 120 / 80

BP to classify as normal

120-139 / 80-89

BP to classify as prehypertension

140 - 159 / 90 - 99

BP to classify as stage 1 hypertension

≥ 160 / 100

BP to classify as stage 2 hypertension

normal

this BP classification is encouraged to have lifestyle modifications

• prehypertension

• stage 1 hypertension

• stage 2 hypertension

BP classification that needs to have lifestyle modification

without compelling indication:

• no antihypertensive drug indicated

with compelling indication:

• drugs for compelling indications

normal BP

• initial drug therapy

  • without compelling indication:

  • with compelling indication:

without compelling indication:

• no antihypertensive drug indicated

with compelling indication:

• drugs for compelling indications

prehypertension

• initial drug therapy

  • without compelling indication:

  • with compelling indication:

without compelling indication:

• thiazide-type diuretics

• ACEI, ARB, BB, CCB, or combination

with compelling indication:

• drugs for the compelling indications

• other antihypertensive drugs (diuretics, ACEI, ARB, BB, CCB) as needed

stage 1 hypertension

• initial drug therapy

  • without compelling indication:

  • with compelling indication:

without compelling indication:

• two drug combination for most (usually thiazide-type diuretics and ACEI or ARB or BB or CCB)

with compelling indication:

• drugs for the compelling indications

• other antihypertensive drugs (diuretics, ACEI, ARB, BB, CCB) as needed

stage 2 hypertension

• initial drug therapy

  • without compelling indication:

  • with compelling indication:

aorta

is the largest artery in the body, acting as the main conduit for oxygenated blood leaving the heart

coronary arteries

are the specific blood vessels branching off the aorta that supply oxygenated blood to the heart muscle itself for it to pump

myocardial infarction

this happens when the coronary arteries are blocked

• diuretics

• b-blockers

• ACE inhibitors

• Ca2+ channel blockers

drugs used in treating hypertension with high coronary disease risk

ARBs

these drugs should NOT be used in treating hypertension with high coronary disease risk

• diuretics

• ACE inhibitors

• ARBs

• Ca2+ channel blockers

drugs used in treating hypertension with diabetes

B-blockers

(since nonselective betablockers affect glucagon production. it converts glycogen into glucose, so px potentially would have hyperglycemia

these drugs should NOT be used in treating hypertension with diabetes

• diuretics

• ACE inhibitors

drugs used in treating hypertension with recurrent stroke

• B-blockers

• ARBs

• Ca2+ channel blockers

these drugs should NOT be used in treating hypertension with recurrent stroke

• diuretics

• b-blockers

• ACE inhibitors

• ARBs

• aldosterone-receptor antagonists

drugs used in treating hypertension with heart failure

• B-blockers

• ACE inhibitors

• aldosterone receptor antagonists

drugs used in treating hypertension with previous myocardial infarction

• diuretics

• ARBs

these drugs should NOT be used in treating hypertension with previous myocardial infarction

• ACE inhibitors

• ARBs

drugs used in treating hypertension with chronic renal disease

• diuretics

• b-blockers

• aldosterone-receptor antagonists

these drugs should NOT be used in treating hypertension with chronic renal disease

1. diuretics

2. BB

3. ace inhibitors

4. ARBs

5. renin inhibitor

6. CCB

7. alpha blockers

8. a/b blockers

9. a2 agonists

10. vasodilators

antihypertensive drugs

diuretics

used as initial drug therapy for hypertension unless there are compelling reasons to choose another agent

decreased blood volume

initial MOA of diuretics is based upon ____, which ultimately leads to decreased blood pressure

true

low dose diuretic therapy is safe, inexpensive, and effective in preventing stroke, myocardial infarction and heart failure

TRUE OR FALSE

serum electrolyte monitoring

this should be done routinely for all px receiving diuretics

• proximal convoluted tubule

• descending and ascending loop of Henle

• distal convoluted tubule

• collecting tubule/duct

4 functional zones in the nephron

1. thiazide diuretics

2. loop diuretics

3. potassium sparing diuretics

3 major classes of diuretics that can help with hypertension

distal convoluted tubule

this is where thiazide diuretics often acts on

• increase sodium and water excretion

  → decrease extracellular volume → decrease CO and renal blood flow

MOA of thiazide diuretics

↓ Na, ↓ H2O = ↓ BV = ↓ CO = ↓ BP

in thiazide diuretics, basically:

↓ Na, ↓ H2O =

decrease in peripheral resistance

long term treatment MOA of thiazide diuretics

• hydrochlorothiazide

• chlorthalidone

thiazide diuretic drugs

• b-blockers

• ACE inhibitors

• ARBs

• potassium sparing diuretics

thiazide diuretics combination therapy includes:

• hypokalemia (can affect heart → heart failure)

• hyperuricemia

• hyperglycemia (lesser extent)

thiazide diuretics side effects

loop of henle

this is where loop diuretics often acts on

• block sodium and chloride reabsorption in the kidneys

  → decreased renal vascular resistance and increased renal blood flow

MOA of loop diuretics

loop diuretics

used even in px with poor renal function or those who have not responded to thiazide diuretics

• furosemide

• torsemide

• bumetanide

• ethacrynic acid

loop diuretic drugs

ethacrynic acid

oldest loop diuretic that is no longer marketed in the Ph

loop diuretics

in combination therapy, this diuretic is rarely used alone to treat hypertension, but they are commonly used (alone) to manage symptoms of heart failure and edema

• hypokalemia

• hypercalcemia

loop diuretics side effects

collecting tubule/duct

this is where potassium sparing diuretics often acts on

potassium-sparing diuretics

this diuretic reduces potassium loss in the urine

• sodium transport blocker

• aldosterone receptor antagonist

MOA of potassium sparing diuretics

(ST.BAT)

• sodium transport blocker

  • amiloride

  • triamterene

(ARASE)

• aldosterone receptor antagonist

  • spironolactone

  • eplerenone

potassium-sparing diuretic drugs

potassium-sparing diuretic

in combination therapy, aldosterone antagonists (one of its MOA) have the additional benefit of diminishing cardiac remodeling that occurs in heart failure. sometimes used in combination with loop diuretics and thiazides to reduce amount of potassium loss induced by these diuretics

• hyperkalemia

• hyperuricemia

• lethargy

• mental confusion

potassium sparing diuretics side effects