Osmotic diuretics

Question 1

MoA

Answer 1

Inhibits sodium and water reabsorption by increasing osmolarity (solute conc.) of blood and renal filtrate.

Osmotic diuretics acts on parts of the nephron that are water soluble:
- proximal convoluted tubule
- descending limb of the loop of henle

Question 2

Mannitol

Answer 2

Pharmacologically inert sugar
Uses:
- Cerebral oedema
- High intracranial pressure

Question 3

Oedema in the elderly

Answer 3

Low-dose diuretic
NOT for long-term use
Try alternatives first e.g. stockings, raising legs, movement