Pharma 9.1 Diuretics and Kidney Failure Drugs

Question 1

In what instances are carbonic anhydrase inhibitors used? How do they work? Why arent they used more frequently?

Answer 1

• Used for glaucoma
• Not used due to risks of metabolic acidosis and hypokalaemia
• Acts on PCT to prevent action of carbonic anhydrase

Question 2

In what instances are osmotic diuretics used? How do they work? Why arent they used more frequently?

Answer 2

• Used in cerebral or pulmonary oedema
• not used as causes excessive water loss and hypernatraemia
• Act to increase osmotic gradient in renal tubules

Question 3

How do ADH antagonists work?

Answer 3

Works by preventing AQP2 from being placed on cell membrane, preventing the water from being taken out of the tubule

Question 4

What are the 5 types of diuretics currently used?

Answer 4

Loop (Furosemide)

Thiazide (Hydrochlorothiazide)

K sparing (Aldosterone antagonists (Spironolactone)/ENaC blockers (Amiloride))

Carbonic anhydrase inhibitors

Osmotic (Mannitol)

Question 5

Give an example loop diuretic. What is its MoA? What is its indications?

Answer 5

• furosemide
• acts on NKCC2 on thin ascending loop of henle.
• Risk of hypokalaemia
• indications - HF, liver failure

Question 6

Give an example thiazide diuretic. What is its MoA? What are its ADRs? Indications? DDI?>

Answer 6

e.g. - chlorothiazide

MoA - Acts on NaCl symporter in DCT. Promotes Ca reabsorption

ADR - hypokalaemia, hypercalcaemia, hyperuricaemia, ED

Indications - HF, hypertension

DDI - Beta blockers, digoxin, steroids all increase risk of ADRs

Question 7

Give an example K sparing diuretic. MoA? DDI?

Answer 7

e.g. - amiloride

MoA - ENaC in DCT and CD.

DDI - ACE inhibitor increases risk of hyperkalaemia

Question 8

Give example aldosterone antagonists. MoA? Indications? ADR?

Answer 8

e.g. - spironolactone

MoA - Inhibition of aldosterone results in less NaKATPase and ENaC synthesis

ADR - hyperkalaemia, gynocomastia

Indications - HF, hypertension, liver failure, hyperaldosteronism e.g. Conns syndrome

Question 9

What drugs would you use for heart failure?

Answer 9

Loop or thiazide diuretic.

ACEi and/or Beta blockers

Question 10

What drugs would you use for hypertension?

Answer 10

Thiazide or aldosterone antagonists

ACEi and/or CCBs

Question 11

What drugs would you use for liver failure?

Answer 11

aldosterone antagonist and loop diuretic

Question 12

What are 4 physiological functions of the kidney?

Answer 12

REEM

Regulatory, Excretory, Endocrine, Metabolism

Question 13

What are the regulatory functions of the kidney?

Answer 13

Fluid balance, acid base balance, electrolyte balance

Question 14

What are the excretory functions of the kidney?

Answer 14

Waste products, drug elimination

Question 15

What are the endocrine functions of the kidney?

Answer 15

Renin-angiotensin-aldosterone, erythropoetin, prostaglandins

Question 16

What are the metabolic functions of the kidney?

Answer 16

Vitamin D, polypeptides (insulin and PTH)