Za Pharmacy
Drugs, Supplies and Delivery
Alteplase
Alteplase is a thrombolytic (clot-busting) medication used to dissolve life-threatening blood clots in conditions like stroke, heart attack, and pulmonary embolism. Marketed under the brand name Activase, it is a recombinant tissue plasminogen activator (tPA) that restores blood flow by breaking down fibrin clots. This article details its mechanism of action, uses, dosage, side effects, precautions, drug interactions, and generic names, referencing the British National Formulary (BNF), Lippincott Textbook of Pharmacology, and Lange Basic & Clinical Pharmacology.
Alteplase works by binding to fibrin in blood clots and converting plasminogen to plasmin, an enzyme that degrades fibrin. This process dissolves clots while minimizing systemic bleeding risks compared to non-fibrin-specific thrombolytics (Lippincott Textbook of Pharmacology).
- Acute Ischemic Stroke:
- Administered within 4.5 hours of symptom onset to restore cerebral blood flow (BNF).
- Myocardial Infarction (Heart Attack):
- Used for ST-segment elevation myocardial infarction (STEMI) to reopen blocked coronary arteries.
- Pulmonary Embolism (PE):
- Treats massive PE with hemodynamic instability.
- Central Venous Catheter Occlusion:
- Clears blocked catheters (off-label use) (Lange Basic & Clinical Pharmacology).
Dosing is indication-specific and weight-based:
- Acute Ischemic Stroke:
- Adults: 0.9 mg/kg (max 90 mg), with 10% as an initial IV bolus and the remainder infused over 60 minutes.
- STEMI:
- Adults ≤67 kg: 15 mg IV bolus, followed by 0.75 mg/kg over 30 minutes (max 50 mg), then 0.5 mg/kg over 60 minutes (max 35 mg).
- Adults >67 kg: 100 mg total (15 mg bolus + 50 mg over 30 minutes + 35 mg over 60 minutes).
- Pulmonary Embolism:
- Adults: 100 mg infused over 2 hours.
Renal/Hepatic Impairment: No dose adjustment required, but use cautiously in severe hepatic dysfunction (BNF).
- Common:
- Bleeding (e.g., gum bleeding, hematomas).
- Hypotension, nausea, or vomiting.
- Serious:
- Intracranial hemorrhage (1–6% risk in stroke patients).
- Severe allergic reactions (e.g., anaphylaxis).
- Reperfusion arrhythmias (post-heart attack) (Lippincott Textbook of Pharmacology).
- Absolute Contraindications:
- Active internal bleeding.
- History of hemorrhagic stroke or intracranial aneurysm.
- Recent major surgery/trauma (within 14 days).
- Relative Contraindications:
- Uncontrolled hypertension (>185/110 mmHg).
- Pregnancy or lactation (use only if benefits outweigh risks).
- Monitoring:
- Vital signs, neurologic status, and signs of bleeding (e.g., hematuria, melena).
- Anticoagulants (e.g., heparin, warfarin): Increased bleeding risk.
- Antiplatelets (e.g., aspirin, clopidogrel): Avoid concurrent use.
- Herbal Supplements (e.g., ginkgo, garlic): Potentiate bleeding.
- Generic Name: Alteplase.
- Brand Names: Activase (US), Actilyse (Europe).
