Cardiac Drugs Flashcards
1
Q
ARB
A
Mechanism of action
- Angiotensin II AT1 receptor blockers
- vasodilation
- reduces secretion of ADH and aldosterone
Indication
- same as for ACEi intolerant of ACEi
SEs
- dizzyness
- headache
- hyperkalaemia
- renal impairment
- abnormal liver fcn
- myalgia
- rash
- diarrhoea
- small cross reactivity with pts who have had angioedema on ACEi
2
Q
Thiazide diuretic
A
Mechanism of action
- inhibit reabsorption of Na and Cl from dist tubules by blocking NaCl symporter
- incr Ca reabsorption from distal tubule (can be helpful in recurrent kidney stones due to hypercalciuria)
Indication
- primary HTN
- indapamide more potent than short acting HCT
- thiazide type significantly lowers CV risk compared to thiazide like
SEs
- hypokalaemia
3
Q
ACEi
A
Mechanism of action
- reduce RAAS activity
- inhibits ACE which is the enzyme that converts angiotensin 1 to 2
- arteriolar vasodilation, preferentially efferent ( reduce eGFR 30%)
- reduces sympathetic activity by reducing plasma norepinephrine
- decreases tubular Na absorption and K excretion->less H2o
- reduces aldosterone and ADH secretion
First line Indications
- systolic HF
- ACS
- proteinuric CKD
SEs
- hypotension
- dry cough (incr in bradykinin)
- nausea
- hyperkalaemia
- worsening renal function
4
Q
Loop diuretics
A
Eg: frusemide, bumetanide, ethacrynic acid ( if allergic to sulfur)
Mechanism of action:
Act on thick ascending limb of loop of Henle
Inhibits Na-K-2CL transporter (compete for Cl- site on carrier) so inhibits NaCl resorption
Parallel reduction in Ca resorption hence increased Ca excretion
Indication
- APO
SEs
- SiADH/hyponatraemia
5
Q
K sparing diuretics
A
Mechanism of action
- Act on cortical collecting tubule to inhibit Na resorption thru aldosterone sensitive Na channels
- Concurrent reductions in K+ and H+ excretion as normally lumen negative electrical gradient favours K+ and H+ secretion
Indication
- Systolic heart failure
SE
- Metabolic acidosis
- Hyperkalaemia
- Gynacomastia ( spirinolactone)
