SCR - Medications

Question 1

Mechanism of action of warfarin ?

Answer 1

Vitamin K antagonist - inhibits the synthesis of vitamin K depending clotting factors factor II, VII, IX, X, protein C and S.

Question 2

Mechanism of action of apixaban ?

Answer 2

Direct clotting factor Xa inhibitor.

Question 3

Why are patients put on anti-coagulant medication ?

Answer 3

Acute MI, AF, DVT, pulmonary embolism, mitral valve stenosis, replacement prosthetic heart valves.

Question 4

What are the side effects of anti-coagulant medication ?

Answer 4

Increased clotting time and risk of haemorrhage.
Check INR - should be between 2-4.

Question 5

Mechanism of action of aspirin ?

Answer 5

Antiplatelet, antipyretic and analgesic - COX-1 and COX-2 inhibitor blocking synthesis of thromboxane.

Question 6

Mechanism of action of beta blockers ?

Answer 6

Blocks beta 1 and 2 receptors blocks adrenaline, slowing signals to the heart - used to reduce blood pressure, HR.
Examples - propranolol (non-selective), atenolol (selective).

Question 7

What are the side effects of beta blockers ?

Answer 7

Lichenoid reactions, exacerbate asthma and heart failure.

Question 8

Why do patients take beta blockers ?

Answer 8

Reduce blood pressure, heart rate, ventricular fibrillation following MI.

Question 9

Mechanism of diuretics ?

Answer 9

Increase salt and water loss in the kidneys to reduce blood volume and cardiac workload.
Examples - Bendroflumethiazide, furosemide.

Question 10

Why do patients take diuretics ?

Answer 10

Hypertension and heart failure.

Question 11

What is the side effects of diuretics ?

Answer 11

Xerostomia and dehydration.

Question 12

Mechanisms of action of lipid lowering drugs ?

Answer 12

HMGcoA reductase inhibitors which inhibit cholesterol synthesis in the liver.
Examples - simvastatin, atorvastatin.

Question 13

Why do patients take lipid lowering drugs ?

Answer 13

High cholesterol.

Question 14

Mechanism of action of an ACE inhibitor ?

Answer 14

Inhibit conversion of angiotensin 1 to 2 (which is a vasoconstrictor).
Triggers aldosterone which promotes salt and water loss and reduction in plasma volume, via renin-angiotensin system.
Example - ramipril, lisnopril.

Question 15

What are the side effects of ACE inhibitors ?

Answer 15

Lichenoid reaction.

Question 16

What are ACE inhibitors used to treat ?

Answer 16

Hypertension and heart failure.

Question 17

Mechanism of action of calcium channel blockers ?

Answer 17

Acts on smooth muscle, blocking calcium channels (calcium channel antagonist) causing vasodilation and reduction in blood pressure and slows conduction.
Example - amlodipine and nifedipine - peripheral vessels, veramipril - central vessels.

Question 18

What is the side effects of calcium channel blockers ?

Answer 18

Gingival overgrowth.

Question 19

Mechanism of nitrates ?

Answer 19

Dilate veins reducing the preload of the heart and resistance of arteries - reduces workload of the heart and afterload and reduces oxygen needs of heart (reduces ischaemic pain).
Example - GTN spray.

Question 20

Mechanism of action of proton pump inhibitors ?

Answer 20

Inhibits the release of acid via the proton pump irrespective of stimulation.
Example - omeprazole, lansoprazole.

Question 21

Mechanism of action of anti-TNF alpha therapy ?

Answer 21

Blocks TNF-alpha inflammatory action - cytokine produced by monocytes during acute inflammation, so controls inflammatory process.
Example - infliximab.

Question 22

Mechanism of action of salbutamol (beta-2 agonist) ?

Answer 22

Beta-2 agonist, binds to receptor causing bronchodilation.

Question 23

Mechanism of action of montelukast ?

Answer 23

Prevents mast cell degranulation.

Question 24

Mechanism of action of beclomethasone MDI ?

Answer 24

Reduces airway oedema, reduces mucous production and improves airway patency.