Cardiac pharmacology Flashcards
How does aspirin work?
Irreversibly acetylates COX
COX is needed for the formation of thromboxane A2, which stimulates platelet activation
Inhibition of COX therefore reduces platelet aggregation, preventing arterial thrombus formation
How does clopidogrel work
Irreversibly inhibits ADP
ADP inhibits adenyl cyclase–> a decreased in cAMP and an increased in intracellular calcium
Increased calcium–> increased platelet aggregation
Used in combination with aspirin or in patients for whom aspirin is contraindicated
When is aspirin used?
For secondary prevention following MI, TIA/stroke, and for patients with angina or peripheral vascular disease
May be used for primary prevention in high risk patients
When is clopidogrel used in conjunction with/instead of aspirin?
Used in patients with high risk of GI bleeding who are unlikely to tolerate aspirin
Used with aspirin after coronary stent insertion and in acute coronary syndrome
Which B blocker is relatively B1 selective?
Bisoprolol
What are the effects of blocking B1 receptors
Negative ionotrophic and chronotropic effect
What are the effects of blocking B2 receptors
peripheral vasoconstriction; bronchoconstriction
In which patients are beta-blockers contraindicated?
Asthma/COPD
Heart block
What are some of the common side effects of beta-blockers?
Cold extremities Fatigue Bronchospasm Bradycardia Erectile dysfunction
What are beta blockers used for?
Angina Hypertension Antidysrhythmic Post-MI (reduced mortality) Heart failure (with caution)
What is furosemide? What is it used for?
Loop diuretic used to treat heart failure
How does furosemide work?
Inhibits resorbtion of NaCl in ascending loop of Henle causing diuresis
What are the side effects of furosemide?
Hyponatraemia Hypotension Hypokalaemia Hypovolaemia/dehydration Hypocalcaemia Ototoxic (may cause deafness)
What is bendroflumethiazide? What it is used for?
Thiazide diuretic used in hypertension
How do the thiazide diuretics work?
Inhibit NaCl resorbtion in the distal tubule–> excretion of Na+ and Cl- with accompanying H2O
