Diuretics

Question 1

What are the four types of diuretics?

Answer 1

Loop diuretics, thiazide duiretics, K-sparing diuretics, osmotics diuretics

Question 2

Name a loop diuretic

Answer 2

furosemide, bumetanide

Question 3

What is mechanism of action of loop diuretics

Answer 3

Block the NaK2Cl co-tansporter in the ascending loop of henle, this increases the solute load in the filtrate ad so increases fluid lost

Question 4

What is the main effect of loop diuretics and what other ions are lost?`

Answer 4

Water is lost along wih NaCl. Ca, K ad H are also lost.

Question 5

What are the clinical uses of loop diuretics?

Answer 5

Loop diuretics are redily absorbed in the gut and so are useful in acute pulmonary oedema.. They are also used in peripheral oedema seen in heart failure. They can also be used to to treat severe hypercalcaemia.

Question 6

What are the side effects of loop diuretics?

Answer 6

Hypokalaemic metabolic acidosis (because of H leaving with K), hypovolaemia, ototoxicity and allergic reactions

Question 7

Name a Thiazide Diuretic

Answer 7

Bendroflumethiazide, indapamide, metolazone

Question 8

What is the mechanism of action f thiazide diuretics?

Answer 8

the inhibit the NaCl channel in the distal convoluted tubule, they also decrease NaCl reabsorption

Question 9

What are the effects of thiazide diuretics? (5)

Answer 9

moderate secretion of water and Na and Cl. They result in low urine Ca by the resorption of urinary Ca (this is the opposite of loop diuretics).Loss of K. Mg is excreted more. Uric acid is excreted less.

Question 10

What are the side effects of Thiazide diuretics?

Answer 10

Hypokalaemia, hyponatraemia, hypomagnesaemia, metabolic alkalosis, hyperglycaemia, increased serum uric acid and lipid levels

Question 11

What are the clinical uses of thiazide diuretics?

Answer 11

Useful in log term treatments (high BP and oedema from heat failure. Can be used to decrease the formation of renal stones due to their resorption of Ca.

Question 12

Name a Potassium sparing duiretic

Answer 12

Spirnolactone, eplerenone, amiloride

Question 13

What is the mechanism of action of K-sparing Diuretics

Answer 13

Spirnolactone and eplerenone are aldosterone antagonists, and so inhibit the Na retaining action of it. Amiloride block sodium chanels in the collecting tubules

Question 14

What are the effects of K-sparing diuretics?

Answer 14

They increase Na excretion while decreasing H and K secretion. Spirnolactone works slow and Alimoride works reletively quickly.

Question 15

What are the clinical uses of K-sparing diuretics?

Answer 15

Used to control the K-wasting effects caused by loop diuretics. Spirnolactone can also be used in hyperadsteronism which is sen in Conn’s and secndary to cirrhosis

Question 16

What are the side effects of K-sparing diuretics?

Answer 16

Hyperkalaemia, ad effects of hypoaldoseronism like gynocomastia

Question 17

Name an Osmotic diuretic

Answer 17

Mannitol

Question 18

What is the mechanism of action of osmotic diuretics?

Answer 18

Manitl is a solute that is freely filtered by the glomerulus but is not reabsorbed, it therefore holds water. the reduction of water reabsorption occurs in the proximal loop of Henle.

Question 19

What are the effects of Mannitol?

Answer 19

Cant reduce brain volume and itracranial pressure by exctracting water from tissue to blood

Question 20

When is mannitol used?

Answer 20

Haemolysis, rhabdomylysis, reducing intra-ocular pressure and intra-crania pressure

Question 21

What are side efects of mannitol?

Answer 21

Na increased, vomitting, nausea headache