Antiplatelet Drugs Flashcards
What are the release products of the light (alpha) granules?
Platelet factor 4
Beta-thromboglobulin
Platelet-derived growth factor (PDGF)
What are the release products of the dense (beta) granules?
Ca+2
Serotonin (5-Hydroxytryptamine)
ATP/ADP
Is primary aggregation reversible? Is secondary?
Primary aggregation is reversible but secondary is NOT.
What are the functions of the anti platelet drugs?
An antiplatelet drug is a member of a class of pharmaceuticals that decreases platelet adhesion, activation and aggregation thereby inhibit thrombus formation.
What is the difference in effectiveness of the anti-platelet drugs in the arterial circulation VS drugs like heparin and warfarin?
These drugs are effective in the arterial circulation, where anticoagulants such as heparin and oral anticoagulants have relatively little effect.
What is the general usage of anti-platelet drugs?
They are widely used in primary and secondary prevention of thrombotic cerebrovascular or cardiovascular disease
Which of the ADP receptor inhibitors are prodrugs?
Ticlopidine
Clopidogrel
Prasugrel
What is the difference between these two ADP receptor inhibitors: Ticagrelor and Cangrelor?
Cangrelor is available via IV only whereas Ticagrelor is oral
What is the most potent class of anti platelet drugs?
GPIIb/IIIa Inhibitors
What are the COX inhibitors?
Aspirin
Celecoxib (COX2 only)
Ibuprofen
Naproxen
What are the ADP receptor inhibitors?
Ticlopidine Clopidogrel Prasugrel Ticagrelor Cangrelor
What are the GP IIb/IIIa inhibitors?
Abciximab
Tirofiban
Eptfibatide
What is a PAR-1 antagonist?
Vorapaxar
What is the difference between the ADP receptor inhibitors Clopidogrel and Prasugrel?
Prasugrel has less population variation in response to treatment so it is more likely to be effective in patients.
How is anti platelet therapy generally administered?
Dual Antiplatelet Therapy as combination therapy often with aspirin. Sometimes even Triple Therapy is used.
What are some of the clinical applications of anti-platelet drugs?
- Cerebrovascular disease:
a. Transient ischemic attack (TIA)
b. Complete stroke - Coronary artery disease:
a. Acute myocardial infarction - Saphenous vein coronary artery bypass grafts
- Venous Thrombosis
- Claudication
- Thrombotic thrombocytopenic purpura
- Prevention of thrombus formation on artificial surfaces
What are some drugs that possibly have interaction with anti-platelet drugs?
- Thrombolytic agents (urokinase, streptokinase and tissue plasminogen activator)
- Heparin/LMW heparin/oral anticoagulants
- Warfarin
- Antithrombin agents (hirudin, bivalirudin and argatroban)
What are the two major pathways of arachidonic acid metabolism?
- Cyclooxygenase pathway
2. Lipoxygenase pathway
What is the main drug that acts on the Cyclooxygenase Pathway?
Aspirin
What are the main products of the Cyclooxygenase Pathway in platelets?
TXA2
What is the main product of the Lipoxygenase Pathway in leukocytes?
Leukotrienes
What are the leukotriene antagonists and what are they used for?
- Montelukast is used for the treatment of asthma and seasonal allergies
- Zarirlukast is used in the treatment of asthma
Aspirin MOA and Route of Administration
COX inhibitor
Oral
Aspirin Indications
ACS, stroke, arterial thrombosis
Aspirin SE
Bleeding
Gastric Irritation
Clopidegrel MOA and Route of Administration
ADP receptor inhibitor
Oral
Clopidogrel Indications
ACS, stroke, in stent thrombosis
Clopidogrel SE
Bleeding, TTP
Prasugrel and Ticagrelor MOA and Route of Administration
ADP receptor inhibitor
Oral
Prasugrel and Ticagrelor Indications
ACS, stroke, in stent thrombosis
Prasugrel and Ticagrelor SE
Bleeding
NSAIDs MOA and Route of Administration
COX inhibitor
Oral
Dipyridamole MOA and ROA
Phosphodiesterase inhibitor
Oral
Dipyridamole Indications
Arterial thrombosis, stroke
Dipyridamole SE
Bleeding
Cilostazol MOA and ROA
Phosphodiesterase inhibitor
Oral
Cilostazol Indications
Intermittent claudication
Cilostazol SE
Hypotension
Abciximab/Eptifibatide/Tirofiban MOA and ROA
GP IIb/IIIa inhibitor
IV
Abciximab/Eptifibatide/Tirofiban Indications
ACS
Coronary Heart Disease
Abciximab/Eptifibatide/Tirofiban SE
Bleeding
Monteleukast MOA and ROA
Leukotriene receptor inhibitor
Oral
Monteleukast Indications
Allergic reactions
Monteleukast SE
Hypotension
Behavioral Changes
Zafirleukast MOA and ROA
Leukotriene receptor inhibitor
Oral
Zafirleukast Indications
Asthma
Zafirleukast SE
Hypotension
Zieuton MOA and ROA
Lipoxygenase inhibitor
Oral
Zieuton Indications
Asthma
Zieuton SE
Hypotension
Which of the following mechanisms represents the antiplatelet actions of Diprydamole?
A. ADP receptor inhibition B. Cyclooxygenase inhibition C. Glycoprotein IIb/IIIa inhibition D. Lipoxygenase inhibition E. Phosphodiesterase inhibition
E. Phosphodiesterase inhibition
