Loop diuretics

Question 1

site of action

Answer 1

loop of Henle

Question 2

prototype

Answer 2

Furosemide

Question 3

Furosemide Mechanism of action

Answer 3

-Acts in the thick segment of the ascending limb of Henle’s loop to block the reabsorption of Na and Cl
-Prevents passive reabsorption of water
-interference here can produce profound diuresis

Question 4

Furosemide
-Routes of administration
-Pharmacokinetics

Answer 4

administered orally, IM, IV
Oral- diuresis within 60 minutes
IV- diuresis within 5 minutes
Hepatic metabolism followed by renal excretion

Question 5

Furosemide
-Therapeutic uses

Answer 5

generally reserved for situations that require rapid or massive metabolism of fluid
-pulmonary edema associated w/ CHF
-edema of hepatic, cardiac, or renal origin that has been unresponsive to less efficacious diuretics
-hypertension that cannot be controlled with other diuretics

Question 6

Furosemide
-adverse effects

Answer 6

-Hyponatremia
-hypochloremia
-dehydration; headache, pain in the chest, calves, or pelvis (thrombosis and embolism)
-hypotension (loss of volume & relaxation of venous smooth muscle)
-hypokalemia (potassium is lost through secretion of Na in distal nephron)
-ototoxicity (loss of hearing)

Question 7

Furosemide Drug Interactions

Answer 7

-Digoxin (used for heart failure)
-Ototoxic drugs
-potassium sparing diuretics

Question 8

Ethacrynic

Answer 8

-promote diuresis by inhibiting Na and Cl reabsorption in the thick ascending limb of the loop of Henle
-approved for edema (caused by HF)
-approved for chronic renal disease
-approved for cirrhosis

Question 9

Bumetamide

Answer 9

-promote diuresis by inhibiting Na and Cl reabsorption in the thick ascending limb of the loop of Henle
-approved for edema (caused by HF)
-approved for chronic renal disease
-approved for cirrhosis

Question 10

Torsemide