Alteplase

What it is and how it works

Mechanism of Action Alteplase is a serine protease responsible for fibrin-enhanced conversion of plasminogen to plasmin. It produces limited conversion of plasminogen in the absence of fibrin. When introduced into the systemic circulation at pharmacologic concentration, alteplase binds to fibrin in a thrombus and converts the entrapped plasminogen to plasmin. This initiates local fibrinolysis with limited systemic proteolysis.

Indications

Activase is a tissue plasminogen activator (tPA) indicated for the treatment of: Acute Ischemic Stroke (AIS). Acute Myocardial Infarction (AMI) to reduce mortality and incidence of heart failure. Limitation of Use in AMI: the risk of stroke may be greater than the benefit in patients at low risk of death from cardiac causes. Acute Massive Pulmonary Embolism (PE) for lysis. Acute Ischemic Stroke Activase is indicated for the treatment of acute ischemic stroke. Exclude intracranial hemorrhage as the primary cause of stroke signs and symptoms prior to initiation of treatment . Initiate treatment as soon as possible but within 3 hours after symptom onset. Acute Myocardial Infarction Activase is indicated for use in acute myocardial infarction (AMI) for the reduction of mortality and reduction of the incidence of heart failure. Limitation of Use: The risk of stroke may outweigh the benefit produced by thrombolytic therapy in patients whose AMI puts them at low risk for death or heart failure.

Dosage and administration (summary)

Acute Ischemic Stroke : The recommended dose is 0.9 mg/kg (not to exceed 90 mg total dose) infused intravenously over 60 minutes with 10% of the total dose administered as an initial bolus over 1 minute. Acute Myocardial Infarction : The recommended total dose is based on patient weight, not to exceed 100 mg. Acute Massive Pulmonary Embolism : The recommended dose is 100 mg administered by IV infusion over 2 hours. Do not add other medications to infusions containing Activase. Acute Ischemic Stroke Administer Activase as soon as possible but within 3 hours after onset of symptoms.

Contraindications

General Active internal bleeding. ( 4.1 , 4.2 ) Recent intracranial or intraspinal surgery or serious head trauma. ( 4.1 , 4.2 ) Intracranial conditions that may increase the risk of bleeding. ( 4.1 , 4.2 ) Bleeding diathesis. ( 4.1 , 4.2 ) Current severe uncontrolled hypertension. ( 4.1 , 4.2 ) Acute Ischemic Stroke Current intracranial hemorrhage. Subarachnoid hemorrhage. Acute Myocardial Infarction or Pulmonary Embolism History of recent stroke.

Warnings and precautions

Increases the risk of bleeding. Avoid intramuscular injections. Monitor for bleeding. If serious bleeding occurs, discontinue Activase. Monitor patients during and for several hours after infusion for hypersensitivity. If signs of hypersensitivity develop, discontinue Activase. Consider the risk of reembolization from the lysis of underlying deep venous thrombi in patients with pulmonary embolism. Cholesterol embolism has been reported rarely in patients treated with thrombolytic agents.

Pregnancy

Pregnancy Risk Summary Published studies and case reports on alteplase use in pregnant women are insufficient to inform a drug associated risk of adverse developmental outcomes.

Storage and supply

Stability and Storage Store lyophilized Activase at controlled room temperature not to exceed 30°C (86°F), or under refrigeration at 2° to 8°C (36° to 46°F). Protect the lyophilized material during extended storage from excessive exposure to light. If stored between 2-30°C (36-86°F), Activase may be used within 8 hours following reconstitution.

Source: Alteplase (Activase) — US FDA prescribing information, 2026-01-20, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.