Loop Diuretics

Question 1

Name the Loop Diuretics

Answer 1

THE MOST EFFICIENT DIURETICS EVA !

Furosemide (SULFA)

Ethacrynic acid (NON-SULFA)

Question 2

Loop Diuretics MOA

Answer 2

Site of action : TAL

• impermeable to water -diluting segment
  (“secured water in car”)
• Blocks NKCC transporter and cancels positive luminal charge
• K+ no longer effluxes from cells thus promote excretion of Mg+2 and Ca+2
• induce expression of COX-2 which synthesizes prostaglandins
• prostaglandins dilate afferent arteriole, increase RBF and enhance diuretic action

Question 3

Loops diuretics are used for …

Answer 3

• 1st line for the symptomatic treatment of acute decompensated heart failure
• 1st line in acute heart failure with orthopnea that has crackles in the lungs and JVD
• loop diuretics treat ascites in liver failure
• can be useful in the treatment of HTN

Question 4

can loop diuretics prolong the the life of the heart ?

Answer 4

No.

Question 5

which group of drugs may interfere with the actions of Loop Diuretics and why ?

Answer 5

NSAIDs - decrease prostaglandins synthesis ,thus interfere with the actions of loop diuretics

Question 6

Side Effects of Loop Diuretics

Answer 6

• loop diuretics may cause hypokalemia
• prolonged use of loop diuretics can cause hypomagenesmia
• Loop diuretics can cause hypocalcemia (rare)
• can cause dose related hearing loss
• Interstitial nephritis can be caused by loop diuretics
• loop diuretics can cause hyperuricemia, may lead to gouty arthritis
• can cause contraction alkalosis