Pharmacology

Question 1

MOA: D-mannitol

Answer 1

Hard for body to process so excreted in urine.

Increases solutes in the filtrate - increases amount of urine.

Question 2

Uses: D-mannitol

Answer 2

• Prior to and during neurosurgery to reduce intracranial pressure
• Decrease elevated intraocular pressure
• Certain cases of renal failure and low urine output

Question 3

Acetazolamide, Methazolamide

Answer 3

Carbonic anhydrase inhibitors

Question 4

Carbonic anhydrase inhibitors

Answer 4

Targets the enzyme carbonic anhydrase in the PCT. No H+/Na+ exchange so Na+ stays in the PCT.

Not potent

Question 5

Furosemide, bumetanide

Answer 5

Loop diuretic

Question 6

Loop diuretics

Answer 6

Inhibit Na+/K+/2Cl- co-transported in ascending loop of hence. Stop the transportation of NaCl out of the tubule into the interstitial tissue. Decreased Na and Cl re-absorption.

• decreases hypertonicity of interstitial
• decreased H20 reabsorption
• increased urine output

Question 7

What is more potent: loop diuretics or carbonic anhydrase inhibitors

Answer 7

Loop diuretics

Question 8

Uses to loop diuretics

Answer 8

pulmonary oedema

chronic heart failure

Question 9

What should loop diuretics be avoided in?

Answer 9

Severe hypokalaemia
Severe hypoatraemia
Anuria
Comatose and pre comatose states associated with liver cirrhosis
Renal failure due to nephrotoxic drugs

Question 10

Bendroflumethiazide

Answer 10

Thiazide diuretic

Question 11

MOA: thiazide diuretic

Answer 11

Targets the Na/Cl co-transported in DCT. More Na+ into collective duct.

Question 12

Uses of thiazide diuretic

Answer 12

Hypertension

Question 13

Low dose vs High dose thiazide diuretic

Answer 13

Low dose: maximal blood pressure lowering effects with little biochemical disturbance
Higher dose: cause more changes in plasma K+, Na+, uric acid, glucose and lipids with little benefit in blood pressure control

Question 14

MOA: aldosterone antagonist

Answer 14

Inhibits Na+ reabsorption through Na+ channels int eh collecting duct.

Question 15

Amiloride, Spironolactone

Answer 15

K+ sparing diuretics

Question 16

Amiloride

Answer 16

Acts on NA channels. No Na-K exchange.

Question 17

What can you not used a K+ sparing diuretic (e.g spironolactone) with and why?

Answer 17

ACE inhibitor. Hyperkalaemia.

Question 18

Finasteride

Answer 18

5 alpha reductase inhibitor

Question 19

MoA Finasteride

Answer 19

Inhibits 5 alpha reductase which converts testosterone into dihydrotestrosterone. Reduces prostate size

Question 20

Tamsulosin

Answer 20

Alpha blocker

Question 21

MoA Tamsulosin

Answer 21

Relaxes sphincter in bladder neck and prostate - easier to urinate

Question 22

oxybutanine, toleterodine

Answer 22

Anti-muscarinics (M3)

Question 23

MoA oxybutanine

Answer 23

Relaxes detrusor muscle, used for urge incontinence

Question 24

alpha-adrenergic agonists MoA

Answer 24

Contracts internal sphincter - used in stress incontinence