Renal Pharmacology (Diuretics)

Question 1

What is the main aim of Diuretic Medications?

Answer 1

Diuretic medications are used to reduce blood pressure.

They do this by reducing reabsoprtion of Na+ (sodium) & water. This means more sodium/water is excreted in the urine, thus decreasing blood volume and blood pressure

Question 2

Describe loop diuretics

(think about- what do they inhibit, what part of the nephron do they work on, and 2 examples of medication names)

Also consider- do patients on loop diuretics have an increased risk of high OR low potassium & sodium levels?

Answer 2

LOOP DIURETICS

What they do- they inhibit the sodium, potassium & calcium transporter, thus reducing sodium & potassium reabsorption

What part of the nephron- loop diuretics inhibit the transporters in the loop of henle

Examples- Frusemide, Lasix

Risk- pts at risk of hypokalaemia (low potassium), hyponatraemia (low sodium)

Question 3

Describe Thiazide Diuretics

(think about- what do they inhibit, what part of the nephron do they work on, and 1 example of medication names)

Also consider- do patients on thiazide diuretics have an increased risk of high OR low potassium, & sodium levels?

Answer 3

THIAZIDE DIURETICS

What they do- they inhibit sodium transporters to reduce sodium reabsorption. They also increase potassium secretion INTO the filtrate

What part of the nephron- thiazide diuretics work block sodium reabsorption in the distal convoluted tubule (DCT)

Example- Hydrochloro-Thiazide

Risk- pts at risk of hypokalaemia (low potassium), and hyponatraemia (low sodium) & hypotension

Question 4

Describe Potassium Sparing Diuretics

(think about- what do they inhibit, how they work, and 1 example of medication names)

Also consider- do patients on potassium sparing diuretics have an increased risk of high OR low potassium levels?

Answer 4

POTASSIUM SPARING DIURETICS:

What they inhibit- they inhibit/block the action of aldosterone

What this does- inhibiting aldosterone means sodium and water cant be reabsorbed and higher levels pass into the collecting ducts and out through the urine. But in doing so, they work to make sure potassium isnt excreted

Example- Spironolactone

Risk- Hyperkalaemia (high potassium levels)