Drugs and their mechanisms Flashcards
(46 cards)
What drug class does clopidogrel belong to and what is its mechanism of action
ANTI-PLATELET
antagonist of the P2Y12 adenosine diphosphate (ADP) receptor, inhibiting the activation of platelets
Which drug class does aspirin belong to and what is its mechanism of action?
ANTI-PLATELET
blocks the action of both cyclooxygenase-1 and 2. Cyclooxygenase is responsible for prostaglandin, prostacyclin and thromboxane synthesis.
(Antiplatelet - inhibits the production of thromboxane)
Which channel do the 4 anti-arrhythmic classes of drugs block?
1 (a,b+c) - all block NA+ channels
2- block b-adrenoceptors
3- block potassium channels
4- block calcium channels
What drug is recommended for the first-line treatment of heart failure and may help to remodel the left ventricle?
ACE inhibitors
Name 3 anticoagulant drugs. Which diseases are they used for?
Warfarin
Heparin
Rivaxoban
Used for DVT / PE / STEMI / AF
Which clotting factors does warfarin block?
2,7,9 and 10
What does rivaroxaban inhibit to cause an anticoagulant effect?
It inhibits factor Xa to prevent the formation of clots
What is the general mechanism of action of diuretics?
Promote sodium and water excretion by inhibiting reabsorption
Loop diuretics are the stronger type of diuretics used in heart failure. An example is furosemide. What is its mechanism of action and where exactly does it have an effect?
Inhibit the Na-K-Cl cotransporter (NKCC) in the thick ascending limb of the loop of Henle, reducing the absorption of NaCl.
Give an example of a thiazide diuretic. These are more mild than loop diuretics and are used to treat hypertension.
Bendrofluazide
B-blockers can be cardio-selective, or non-cardioselective. Name an example from each category.
Cardioslective - Bisoprolol and atenolol
Non cardioselective - Propranolol
What is the mechanism of action of Beta blockers?
Block B1 receptors reducing contractiity and therefore oxygen demand
They have a negative inotropic and chronotropic effect
Name 3 calcium channel blockers
Amlodopine
Verapamil
Diltiazem
Describe the mechanism of action of calcium channel antagonists
Block a1 receptors, block calcium influx and cause vasodilation - increases perfusion of the myocardium
What can calcium channel antagonists be used to treat?
Hypertension
Arrhythmias
Angina
What are the 3 main classes of vasodilators? Give an example of each
Alpha blockers - prazosin
Ace inhibitors - lisinopril
ARBs -losartan
What is the mechanism of action of ACE inhibitors?
Blocks conversion of angiotensin I to angiotensin II
What is the mechanism of action of ARBs?
Blocks the action of angiotensin II
Name a potassium channel opener and describe its mechanism of action and what its used for
- Nicorandil
- Decreases the calcium sensitivity of smooth muscle causing relaxation of smooth muscle and coronary vasodilation
- Used to treat stale angina
What is the mechanism of action of ivabridine and when is it used?
- Prolongs diastole by inhibiting the If current.
- It decreases HR and increases SV
- ONLY WORKS IF THE PATIENT IS IN SINUS RHYTM
GTN (short acting) and isorbide mononitrate (longer acting) are nitrates used to manage angina and acute heart failure. Describe their mechanism of action.
VASODILATORS
MECHANISM;
- Cause release of nitric oxide in smooth muscle, increasing cGMP which leads to a fall in intracellular calcium levels - causes relaxation of the cardiac muscle
- Dilate the coronary arteries (increases perfusion to ischaemic zones)
- Decrease preload and afterload by dilating arteries and veins
Name a fibrinolytic drug and state what it is used for?
Streptokinase
- Used to dissolve clots
- Used to treat STEMI and PE
List 4 anti-cholesterol drug classes and give examples
Statins - Atorvastatin
Fibrates - Bezafibrate
Bile acid binding resins - Colestipol
Ezetimibe
What is the mechanism of action of statins?
Blocks the HMG CoA reductase enzyme
Reduces production of LDL and increases its clearance
