Anticoagulants

Question 1

Aspirin (ASA)

Answer 1

Class: Nonopoid analgesic; antipyretic, platelet aggregation inhibitor

MOA: Inhibits synthesis of protstaglandins to reduce pain and fever, does not have significant anti-inflammatory properties, blocks formation of thromboxane A2 which causes platelate aggregation and aterial constriction

Pharmacokinetics: Well absorbed orally, onset 5-30 min, duration 1-4 hours, HL: 15-20 min

Indications: Mild pain, Fever, chest pain suggesting ACS

AR/SE: Liver Failure and Hepatotoxicity with overdose; renal failure with chronic use, GI bleeding

Contraindications: Known hypersensitivity

Dosage: 325 (4 x 81mg = 324 mg)

Special Considerations: (P Class D in 1st Trimester)

Question 2

Heparin

Answer 2

Class: anticoagulant, antithrombotic

MOA: potentiates inhibitory effect of antithrombin

Pharmacokinetics: onset-IV immediate; duration- 2-6 hours; Hl: 90 min.

Indications: prophylaxis and treatment of various thromboembolic disorders; inhibit clot formation in ACS.

AR/SE: bleeding, anemia, thrombocytopenia

Contraindications: known allergy; uncontrolled bleeding, severe thrombocytopenia or open wounds

Dosage: 60 U/kg IV, followed by 12 U/kg/hr

Special Considerations: (P class C) double check dosages!!

Question 3

Enoxaparin (Lovenox)

Answer 3

Class: anticoagulant

MOA: accelerates the formation of antithrombin and deactivates thrombin; prevents fibrinogen from converting to fibrin

Pharmacokinetics: onset-3-5 hours; duration- varies; Hl: 4.5 hours

Indications: inhibit clot formation in acute ACS (STEMI, NSTEMI, unstable angina), pulmonary embolism and DVT

AR/SE: bleeding, anemia, thrombocytopenia

Contraindications: known allergy; uncontrolled bleeding, severe thrombocytopenia or open wounds

Dosage: 30 mg IV plus a 1 mg/kg SC dose (SC dose repeated Q 12 HRS)

Question 4

Clopidogrel plavix

Answer 4

Class: antiplatelet, platelet aggregation inhibitor

MOA: inhibits platelet aggregation by inhibiting the binding of ADP to platelet receptors

Pharmacokinetics: Onset within 2 hrs; duration 7-10 days following discontinuation

Indications: reduction of atherosclerotic events in pts at risk including recent MI, ACS, stroke

AR/SE: GI bleeding, bleeding, neutropenia, chest pain, fatigue, depression, epistaxis

Contraindications: known allergy, pathological bleeding disorders

Dosage: 300 mg loading dose, followed by 75 mg daily

Question 5

TNKase & TPA

Answer 5

Class: thrombolytic, plasminogen activator

MOA: converts plasminogen to plasmin, which then degrades fibrin in blood clots

Pharmacokinetics: onset- within minutes, duration unknown

Indications: treatment of acute Mi an acute stroke

AR/SE: intracranial hemorrhage, gi bleeding, retroperitoneal bleeding, gu tract bleeding, anaphylaxis

Contraindications: known allergy, hx of stroke, recent intracranial or intraspinal injury or trauma, intracranial neoplasm, av malformation, aneurysm

Dosage: per medical direction

Special Considerations: (p class C) use with blood thinner increases risk of bleeding.