10 Antihypertensive drugs

Question 1

Thiazide diuretics- Names

Answer 1

Hydrochlorothiazide
Indapamide
Chlorthalidone

Question 2

Thiazide diuretics-MoA

Answer 2

They increase sodium and water excretion and thus lower BP by two mechanisms related to this:

1. Decrease blood volume and thereby decrease cardiac output
2. With continued administration over weeks/months, they also decrease PVR, due to reduction in the sodium content of arteriolar smooth muscle cells, which decreases muscle contraction in response to vasopressor agents such as norepinephrine and angiotensin

Question 3

Thiazide diuretics- Clinical use

Answer 3

Treatment of mild to moderate hypertension

• Hydrochlorothiazide->Initial treatment of mild to moderate HPT
• Indapamide->Como with angiotensin inhibitors to control BP to reduce risk of stroke and MI

Question 4

Thiazide diuretics-Adverse effects

Answer 4

Hypokalemia-> cardiac arrhythmias and muscle weakness.
Elevate plasma levels of: glucose, uric acid and lipids in some pat.
Hematologic toxicity
Aggravate hepatic disease and diabetes
Compensatory increase in renin secretion(Should use angiotensin inhibitor in combo with them)

Question 5

Thiazide diuretics- Interactions

Answer 5

• Increase serum levels of lithium->Lithium toxicity

- Hypotensive effect is decreased by NSAIDS and increased by ACE inhibitors

Question 6

Thiazide diuretics- Specials

Answer 6

• Reduces BP by 10-15 mm Hg
• Protect against osteoporosis (decrease ca excretion)
• Cheap drugs

Question 7

Loop diuretics- Clinical use

Answer 7

Reserved for hypertensive pt who have poor renal function and serum creatinine more than 2,3mg/dL

Question 8

Potassium-sparing diuretics- Names

Answer 8

Amiloride
Spironolactone
Eplerenone
Triameterene

Question 9

Potassium-sparing diuretics- MoA

Answer 9

Mild natriuretic effect, and they reduce renal potassium excretion and thereby prevent hypokalemia caused by thiazide and loop-diuretics
-Spironolactone and eplerenone are mineralocorticoid receptor antagonists

Question 10

Potassium-sparing diuretics- Clinical use

Answer 10

• Hypertension that cannot be controlled with combo of three or more drugs
• Aldosteronism and heart failure

Question 11

Potassium-sparing diuretics- Adverse effects

Answer 11

Hyperkalemia

Question 12

Potassium-sparing diuretics- Interactions

Answer 12

Hyperkalemic effect is increased by ACE inhibitors and potassium supplements

Question 13

Alpha blockers-Clinical use

Answer 13

Not used in initial treatment of HPT, but can be added to other drugs when BP is not adequately controlled

Question 14

Alpha blockers- Adverse effects

Answer 14

• Reflex tachycardia and contractile force (may increase myocardial oxygen demand)
• Fluid retention and orthostatic hypotension

Question 15

Alpha blockers- interaction

Answer 15

Hypotensive effect is increased by beta blockers and diuretics

Question 16

Beta blockers- Clinical use

Answer 16

Hypertensive pt with cardiovascular diseases such as CAD, MI and heart failure

Question 17

Beta blockers- Adverse effects

Answer 17

• Bronchospasm (avoid in COPD or use selective)
• Hypoglycemia in excessive insulin administration and blockade of early signs of hypoglycemia (caution in pt with diabetes)
• Decreased peripheral blood flow during exercise and risk of cold extremities

Question 18

Beta blockers- Interactions

Answer 18

Hypotensive effect is decreased by NSAIDS

Question 19

Centrally acting drugs- Names

Answer 19

Clonidine
Guanfacine
Methyldopa

Question 20

Centrally acting drugs-MoA

Answer 20

Activates a2 receptors in brainstem and decrease sympathetic outflow, and vascular resistance

Question 21

Centrally acting drugs-Clinical use

Answer 21

Clonidine->Hypertensive urgencies and decrease withdrawal symptoms
Methyldopa-> Hypertension in pregnant women

Question 22

Centrally acting drugs-Adverse effects

Answer 22

Sedation, dry mouth, impaired mental acuity and rebound hypertension (if drug is discontinued abruptly)
-Methyldopa->Immunologic effects (Coombs positive hemolytic anemia and autoimmune hepatitis)

Question 23

Centrally acting drugs-Interactions

Answer 23

-Hypotensive effect decreased by TCA
-Sedative effect increased by CNS depressants
Methyldopa->Hypotensive effect increased by levodopa

Question 24

ACE inhibitors- names

Answer 24

Benazepril
Enalapril
Quinepril
Ramipril
Fosinepril
Lisinopril
Captopril

Question 25

ACE inhibitors- MoA

Answer 25

They inhibit angiotensin-converting enzyme and thus the production of angiotensin II. This leads to several effects; 1. Decreased vasoconstriction and thus decreased vascular resistance both in arteries (decreased afterload), and veins (decreased preload). 2. Reduce aldosterone secretion, sodium and water resorption, norepinephrine release and leads to potassium retention. 3. Inhibits inactivation of bradykinin by ACE and thus vasodilation

Question 26

ACE inhibitors- Clinical use

Answer 26

Hypertension in Heart failure, MI, CKD, and DM patients

Question 27

ACE inhibitors. Adverse effects

Answer 27

Fetal injury and death, renal failure in pt with bilateral renal artery stenosis, dry cough, angio edema, rash and abnormal taste

Question 28

ACE inhibitors- Contraindication

Answer 28

Pregnancy

Question 29

ACE inhibitors- Interactions

Answer 29

- Antihypertensive effect is increased by diuretics and CCBs - Lithium toxicity - Hyperkalemic effect is increased by PS-diuretics and potassium supplements - Hypotensive effect is decreased by NSAIDs

Question 30

ACE inhibitors-Specials

Answer 30

- All except captopril and lisinopril are prodrugs | - Enalaprilat is available IV, the rest is taken orally

Question 31

Angiotensin receptor blockers-Names

Answer 31

``` Valsartan irbesartan Losartan Telmisartan Candesartan ```

Question 32

Angiotensin receptor blockers-MoA

Answer 32

These drugs selectively block AT1 receptors in various tissues and thereby reduce vasoconstriction, aldosterone secretion, sodium reabsorption by the proximal tubule and norepinephrine release from sympathetic nerve terminals.

Question 33

Angiotensin receptor blockers-Clinical use

Answer 33

Hypertension (reduce cardiovascular consequences including, LVH and stroke)

Question 34

Angiotensin receptor blockers-Adverse effects

Answer 34

Hyperkalemia, neutropenia, elevated aminotransferases, and fetal injury

Question 35

Angiotensin receptor blockers-Contraindication

Answer 35

Pregnancy

Question 36

Direct renin inhibitor name and clinical use

Answer 36

- Aliskiren | - Hypertension

Question 37

Calcium channel blockers-Name

Answer 37

``` Diltiazem verapamil amlodipine felodipine isradipine nicardipine nifedipine ```

Question 38

Calcium channel blockers-MoA

Answer 38

By blocking calcium ion channels in the plasma membranes of smooth muscle, the ccbs relax vascular smooth muscle and causes vasodilation. They have greater effect on arteriolar smooth muscle then venous, effect on BP is mainly because a reduction in PVR.

Question 39

Calcium channel blockers-Clinical use

Answer 39

Hypertension, angina pectoris, peripheral vascular disorders, cardiac arrhythmias - Hypertension pt with asthma - Protect against stroke, CAD and kidney disease

Question 40

Calcium channel blockers-Adverse effects

Answer 40

Dihydropyridine drugs may cause reflex tachycardia and gingival hyperplasia

Question 41

Hydralazine and minoxidil- MoA and clinical use

Answer 41

- Vasodilator | - Hypertension and alopecia

Question 42

Hydralazine and minoxidil- Adverse effects

Answer 42

When used alone->Reflex tachycardia, fluid retention, and precipitation of angina in susceptible pt (Combine with diuretic + beta blocker or sympatholytic agent) - Hydralazine-> Lupus like syndrome - Minoxidil->Hypertrichosis

Question 43

Nitroprusside- Moa and clinical use

Answer 43

- Vasodilator | - Management of hypertensive emergencies

Question 44

Fenoldopam- Moa, clinical use and adverse effects

Answer 44

- Dopamine D1 agonist that leads to vasodilation in coronary, renal and mesenteric vessels - Hypertensive emergencies - Reduce potassium levels in blood