Drug Information: Tirofiban
Tirofiban is a non-peptide tyrosine derivative and a reversible antagonist of the platelet GP IIb/IIIa receptor. It is an antiplatelet drug primarily used in acute coronary syndromes and during percutaneous coronary intervention (PCI) to prevent platelet aggregation and thrombus formation. It works by inhibiting the binding of fibrinogen to the GP IIb/IIIa receptor on platelets, thereby preventing platelet aggregation.
Category
Antiplatelet
Mechanism of Action
Tirofiban acts as a Glycoprotein IIb/IIIa (GP IIb/IIIa) receptor antagonist. The GP IIb/IIIa receptor is the major platelet surface receptor involved in the final common pathway of platelet aggregation. Upon platelet activation, this receptor undergoes a conformational change, allowing it to bind fibrinogen, von Willebrand factor (vWF), and other adhesive ligands. These ligands act as bridges between adjacent platelets, leading to platelet aggregation and thrombus formation.
Tirofiban competitively and reversibly binds to the GP IIb/IIIa receptor, preventing the binding of fibrinogen and vWF. By blocking this interaction, Tirofiban inhibits platelet aggregation, thereby reducing the risk of thrombotic events. Its reversible binding allows for relatively rapid restoration of platelet function upon discontinuation of the drug, which can be advantageous in certain clinical situations.
Clinical Uses
Tirofiban is primarily used in the management of acute coronary syndromes (ACS), including unstable angina and non-ST-segment elevation myocardial infarction (NSTEMI), particularly when a percutaneous coronary intervention (PCI) is planned. It is also indicated during PCI, such as angioplasty and stenting, to prevent abrupt vessel closure and ischemic complications. Its use has been shown to reduce the risk of death, myocardial infarction, and urgent revascularization in patients undergoing these procedures. Furthermore, it may be considered in high-risk patients with acute coronary syndromes who are not immediately undergoing PCI but are at high risk for thrombotic events.
Dosage
Adults: The typical dosage regimen for Tirofiban involves an initial intravenous bolus of 25 mcg/kg administered over 3-5 minutes, followed immediately by a continuous intravenous infusion of 0.15 mcg/kg/min for up to 18 hours, particularly during PCI. An alternative regimen involves a higher initial bolus of 0.4 mcg/kg administered over 30 minutes, followed by a continuous infusion of 0.1 mcg/kg/min. The choice of regimen depends on clinical circumstances and institutional protocols.
Pediatrics: Tirofiban use in pediatric patients is generally not well-established, and dosing recommendations may vary significantly or be based on limited data. Consultation with a specialist is essential when considering Tirofiban use in children.
Route of Administration: Intravenous (IV)
Indications
* Acute Coronary Syndrome (ACS)
* Unstable Angina
* Non-ST-Segment Elevation Myocardial Infarction (NSTEMI)
* Percutaneous Coronary Intervention (PCI)
* Prevention of Thrombotic Complications During PCI
Contraindications
* Active bleeding
* History of intracranial hemorrhage
* Severe uncontrolled hypertension
* Significant thrombocytopenia (platelet count < 150,000/mm3)
* Major surgical procedure or severe trauma within the previous month
* Hypersensitivity to tirofiban or any of its components
* History of bleeding diathesis
* Severe liver disease
* Acute stroke within 30 days
FAQ
Q: What is Tirofiban used for?
A: Tirofiban is used to prevent blood clots in patients with acute coronary syndromes (ACS) and during percutaneous coronary intervention (PCI).
Q: How does Tirofiban work?
A: Tirofiban works by blocking the GP IIb/IIIa receptors on platelets, preventing them from clumping together and forming clots.
Q: What are the common side effects of Tirofiban?
A: The most common side effect is bleeding. Other potential side effects include thrombocytopenia (low platelet count) and allergic reactions.
Q: How is Tirofiban administered?
A: Tirofiban is administered intravenously (IV) as a bolus followed by a continuous infusion.
Q: Can Tirofiban be used in patients with kidney problems?
A: The dose of Tirofiban should be adjusted in patients with kidney problems to prevent bleeding complications. Careful monitoring is required.
Q: What should I tell my doctor before taking Tirofiban?
A: Tell your doctor about any bleeding disorders, recent surgeries or trauma, kidney problems, or allergies you have. Also, inform them of any other medications you are taking, including over-the-counter drugs and supplements.
Q: How long does Tirofiban stay in my system?
A: Tirofiban has a relatively short half-life, and its effects typically wear off within a few hours after the infusion is stopped, allowing platelet function to recover.
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