LOOP DIURETIC

Question 1

LOOP DIURETIC - examples

Answer 1

Furosemide

Bumetanide

Question 2

LOOP DIURETIC - indications (3)

Answer 2

1. Chronic heart failure
2. Acute pulmonary oedema
3. other general Oedematous states.

Question 3

LOOP DIURETIC - MOA

Answer 3

Act on the ascending LoH where they inhibit the Na+/K+/2Cl- cotransporter =

preventing reabsorption if Na+ / K+ =

this means that more Na+/K+ and H20 remain in the filtrate to be excreted out in the urine = potent diuretic effect

Direct effect on blood vessels causing dilatation of capacitance veins. In acute heart failure this reduces preload (blood returning to the heart) which means less “work” for the heart AND it improves contractile function of the “overstretched/overworked” heart muscle –> this is the main benefit of these diuretics in acute heart failure

Question 4

LOOP DIURETIC - adverse effects

Answer 4

→ Dehydration
→ Hypotension
→ Low electrolyte state

Question 5

LOOP DIURETIC - adverse effects at higher doses

Answer 5

Ototoxicity:

→ Hearing loss
→ Tinnitus

Question 6

LOOP DIURETIC - interactions

Answer 6

Drugs that are excreted by the kidney

→ Lithium (increased nephrotoxicity)

→ Digoxin (increased nephrotoxicity)

→ Aminoglycosides (increased ototoxicity and nephrotoxicity)

Question 7

LOOP DIURETIC - (cautions)

Answer 7

→ Hepatic encephalopathy
→ Severe hypokalaemia
→ Hyponatraemia
→ Gout (can worsen it)

Question 8

LOOP DIURETIC - contraindications (avoid)

Answer 8

→ Severe hypovolaemia

→ Dehydration