Diuretics

Question 1

Diuretics used as antihypertensive drugs

Answer 1

Thiazide diuretics
Loop-diuretics
Potassium-sparing diuretics

Question 2

Diuretics - MOA

Answer 2

Increase renal Na excretion (natriuresis)

Question 3

Which group of diuretics is most frequently used in HT?

Answer 3

Thiazide diuretics. Despite medium natriuretic effect they are more effective than loop-diuretics, which are more natriuretic.

Question 4

Loop-diuretics - Adverse effects

Answer 4

Generally greater potential for hyponatremia.

Question 5

Thiazide diuretics - MOA

Answer 5

Decrease blood volume by increased natriuresis.
Decrease PVR on long-term basis by reduction of sodium in arterial smooth muscle cells. This decreases the vascular smooth muscle contraction in response to vasopressors.

Question 6

How much does thiazide diuretics typically reduce the blood pressure?

Answer 6

10-15 mmHg.

Question 7

Thiazide diuretics - 3 drugs

Answer 7

Hydrochlorothiazide
Indapamide
Chlorthalidone

Question 8

Indapamide - benefits

Answer 8

Also calcium channel blockade which causes vasodilation

Question 9

Indapamide may be efficiently combined with..

Answer 9

Angiotensin inhibitors.

Question 10

Hydrochlorothiazide - indications

Answer 10

Mild/moderate HT - initial treatment.

Question 11

Thiazides - adverse effects

Answer 11

Hypokalemia (cardiac arrhythmias and muscle weakness).
Elevate glucose, uric acid, lipids.
Hematologic toxicity, aggravate hepatic disease and diabetes.
Compensatory increase of renin secretion.

Question 12

Dosing of thiazide diuretics - general

Answer 12

Higher dose cause more side effects, but no greater effect on BP.

Question 13

Advantage of thiazides

Answer 13

May protect against osteoporosis by decreasing Ca excretion

Question 14

Loop diuretics - indications in HT

Answer 14

Reserved for HT with poor renal function and serum creatinine > 2.3mg/dL. OR when thiazide diuretic is ineffective/contraindicated

Question 15

Potassium-sparing diuretics - 4 drugs

Answer 15

Amiloride.
Spironolactone.
Eplerenone.
Triamterene.

Question 16

Potassium-sparing diuretics - indications

Answer 16

Prevent hypokalemia.

Spironolactone, eplerenone: HT that cannot be controlled with 3 or more drugs.

Question 17

Difference between eplerenone and spironolactone

Answer 17

Eplerenone has fewer endocrine adverse effects and it may cause regression of microalbuminemia.

Question 18

Diuretic preferred in management of hypertension in pts with diabetes type 2

Answer 18

Eplerenone.

Question 19

Cardiovascular effects of diuretics used in hypertension (PVR, CO, blood volume, renin activity)

Answer 19

PVR: decrease.
Cardiac output: decrease.
Blood volume: decrease.
Renin activity: Increase.

Question 20

Thiazide and loop diuretics - effect on serum potassium and cholesterol measurements

Answer 20

Serum K: decrease
Total cholesterol: increase
LDLs: increase
TGs: Increase

Question 21

Potassium-sparing diuretics - effect on serum potassium

Answer 21

Serum K: Increase

Question 22

Thiazide diuretics and loop diuretics - interactions

Answer 22

Increase lithium levels.
NSAIDs: decreases hypotensive effect.
ACE inhibitors: increased hypotensive effect