Drugs

Question 1

What are ACE inhibitors used for?

Answer 1

HTN (1st in younger pts)
HF
diabetic nephropathy
secondary prevention of IHD

Question 2

ACE inhibitor mechanism of action

Answer 2

inhibits conversion of angiotensin I to angiotensin II
- decrease in angiotensin II lvls leads to vasodilation and reduced bp
- decrease reduces stimulation for aldosterone release, decrease in sodium and water retention by kidneys
Renoprotective mechanism - angiotensin II constricts efferent glomerular arterioles, so ACE inhibitors therefore lead to dilation of efferent arterioles -> reduced glomerular capillary pressure -> decreased mechanical stress on delicate filtration barriers of glomeruli

Question 3

ACE inhibitors adverse effects

Answer 3

cough - thought to be due to increased bradykinin lvls
angioedema
hyperkalaemia
first-dose htn

Question 4

ACE inhibitors monitoring

Answer 4

urea and electrolytes should be checked before starting and after increasing the dose
rise in creatinine and potassium may be expected, acceptable = increase up to 30% from baseline for creatinine, and potassium increase up to 5.5 mmol/l

Question 5

Beta blockers indications

Answer 5

angina
post MI
HF
arrhythmia
HTN
thyrotoxicosis
migraine prophylaxis
anxiety

Question 6

Beta blockers contraindications

Answer 6

uncontrolled HF
asthma
sick sinus syndrome
concurrent verapamil use - may precipitate severe bradycardia

Question 7

Beta blockers adverse effects

Answer 7

cold peripheries
fatigue
sleep disturbance, nightmares
erectile dysfunction

Question 8

What is digoxin?

Answer 8

cardiac glycoside mainly used for rate control management in AF
+ve inotropic properties sometimes used for improving symptoms in HF

Question 9

Digoxin mechanism of action

Answer 9

decreases conduction through AV node, slows ventricular rate in AF and flutter
increases force of cardiac muscle contraction due to inhibition of Na+ / K+ ATPase pump. also stimulates vagus nerve
Has narrow therapeutic index

Question 10

Digoxin adverse effects

Answer 10

Toxicity - pt feels unwell, lethargic, N&V, arrhythmias, gynaecomastia

Question 11

Loop diuretics mechanism of action

Answer 11

inhibit Na-K-Cl co-transporter in thick ascending limp of loop of Henle, reducing NaCl absorption
2 variants of NKCC: loop diuretics act on NKCC2, which is more prevalent in kidneys

Question 12

Loop diuretics indications

Answer 12

HF - both acute and chronic
resistant HTN, particularly in pts w/ renal impairment

Question 13

Loop diuretics adverse effects

Answer 13

htn
hyponatraemia
hypokalaemia, hypomagnesaemia
hypochloraemic alkalosis
ototoxicity
hypocalcaemia
renal impairment
hyperglycaemia
gout