Unit 2 Pharmacology

Question 1

Anticoagulants

Answer 1

• unfractionated heparin
• low molecular weight heparin
• enoxaparin (LMWH) -fondaparinux
• warfarin
• dabigatran
• rivaroxaban

Question 2

Antiplatelet Agents

Answer 2

• aspirin
• plus choice of P2Y12 inhibitor (ADP antagonists)
  
  • clopidogrel-prasugral
  • ticagrelor
• if procedding to cath or high risk, consider addition of G2B2A inhibitor
  
  • eptifibatid-tirofiban
  • abciximab

Question 3

High Molecular Weight Heparin (Unfractionated)

Answer 3

• MOA: anticoagulant, needs to bind to anti-thrombin 3 (indirect lot inactivates IIa and Xa)
• Pharmacokinetics: parenteral, IV or SC, half life is zero order (dose dependent)
• Uses: drug of choice in pregnancy, anticoagulant, ACS, VTE
• Adverse: hemorrhage, thrombocytopenia
• Overdose: protamine
• Drug-drug interactions: NSAIDs inc. bleeding risk with all anticoagulants
• Disadvantages:

Question 4

Enoxaparin (LMWH)

Answer 4

• MOA: binds ATIII and inactivates Xa
• Pharmacokinetics: parenteral, daily dosing, first order renal elimination, IV or SC
• Uses: anticoagulant, ACS, VTE
• Adverse: hemorrhage, thrombocytopenia
• Overdose: protamine (less effective)
• Drug-drug interactions: antiplatelet agents
• Disadvantages:

Question 5

Warfarin

Answer 5

• MOA: vitamin K antagonist, acts in liver to prevent synthesis of clotting factors (II, X), anticoagulant
• Pharmacokinetics: slower onset of action, long half life, vitamin K dependent, oral
• Uses: A fib, VTE prophylaxis
• Adverse: category X, hemorrhage, contraindicated in pregnancy
• Overdose: vit K, FFP, PCC, rVIIa
• Drug-drug interactions: inc effect: CYP450 inhibitors
• Disadvantages:

Question 6

Dabigatran

Answer 6

• MOA: acts in plasma to directly inhibits thrombin (factor IIa), and factor Xa, prodrug
• Pharmacokinetics: peak 1-2 hours, oral, renal and hepatic elimination
• Uses: anticoagulant, A fib
• Adverse: category C, bleeding, GI complaints, fewer drug or food interactions that with warfarin
• Overdose: hemostatic measures: FF (fresh frozen plasma), RBCS
• Drug-drug interactions:
• Disadvantages:

Question 7

Rivaoxaban

Answer 7

• MOA: onset 2.5-4 hrs, act in plasma to directly inhibit factor Xa, anticoagulant
• Pharmacokinetics:
• Uses:anticoagulant
• Adverse: category C, bleeding
• Overdose: hemostatic measures: FF (fresh frozen plasma), RBCS
• Drug-drug interactions:
• Disadvantages:

Question 8

Aspirin

Answer 8

• MOA: low dose is cox 1 selective, antiplatelet, irreversible COX1 block of ADP inhibition receptor
• Pharmacokinetics: po
• Uses: acute MI, unstable angina, PCI, secondary prevention of MI, secondary prevention of ischemia stroke, essential for both primary and secondary prevention of all major adverse coronary events
• Adverse: GI upset, bleeding, rare with low dose therapy
• Drug-drug interactions: inc. bleeding with anticoagulants

Question 9

P2Y12 inhibitor (ADP receptor inhibitor)

 - clopidogrel-prasugrel
 - ticagrelor

Answer 9

• MOA: ADP antagonists (block ADP receptor), use with aspirin, antiplatelet
• Pharmacokinetics: oral qd/bid
• Uses: acute MI (w/aspirin), unstable angina (w/ aspirin), PCI (w/ aspirin)
• Adverse: bleeding, dyspepsia, dypnea
• Overdose:
• Drug-drug interactions:
• Disadvantages: ticagrelor (bradycardia), clopidogrel (bleeding)

Question 10

P2Y12 inhibitor (ADP receptor inhibitor)

 - clopidogrel-prasugrel
 - ticagrelor

Answer 10

• MOA: ADP antagonists (block ADP (P2Y12) receptor), use with aspirin, antiplatelet
• Pharmacokinetics: oral qd/bid
• Uses: acute MI (w/aspirin), unstable angina (w/ aspirin), PCI (w/ aspirin)
• Adverse: bleeding, dyspepsia, dypnea
• Overdose:
• Drug-drug interactions: no ddi with P + PPIs
• Disadvantages:

Question 11

G2B3A inhibitor

 - eptifibatid-tirofiban 
 - abciximab

Answer 11

• MOA: inhibition of G2b/3a receptor, anti-platelet
• Pharmacokinetics: parenteral infusion
• Uses: PCI (with aspirin and ADP antagonist)
• Adverse: bleeding
• Drug-drug interactions: NA

Question 12

Statins

Answer 12

-high doses make myositis (muscle pain) more likely

Question 13

Dipyridamole

Answer 13

MOA: inhibits phosphodiesterase in platelets, inc cAMP, anti aggregation effect
Pharmaco: oral
Adverse: dizziness
DDIs: NA
Uses: secondary prevention MI, stroke

Question 14

Secondary Prevention After MI

Answer 14

• aspirin (with or without clopidogrel or other thienopyridines)
• statin
• beta blocker
• ACE inhibitor
• smoking cessation

Question 15

Diuretics

Answer 15

• furosemide- loop diuretic (most effective) (K wasting)
• hydrochlorathiazide- (K wasting)
• spirolactone (gynecomastia) (K wasting)

Question 16

Dipyridamole

Answer 16

• works by inhibiting phosphodiesterase leading to increased levels of cAMP and therefore increased levels of PGI2
• antiplatelet