Indications
Alteplase is used to treat acute ischemic stroke. Before treatment starts, intracranial hemorrhage must be excluded as the primary cause of the stroke signs and symptoms. Treatment should begin as soon as possible, and within 3 hours after symptom onset. Alteplase is also used in acute myocardial infarction (AMI), to reduce mortality and to reduce the incidence of heart failure. For pulmonary embolism, alteplase is used for the lysis of acute massive pulmonary embolism. This is defined as acute pulmonary emboli obstructing blood flow to a lobe or multiple lung segments. It is also defined as acute pulmonary emboli accompanied by unstable hemodynamics, for example when blood pressure can't be maintained without supportive measures.
⚠️ Always consult a registered physician before taking any medicine.
Pharmacology
Alteplase is a serine protease. It converts plasminogen to plasmin, and fibrin makes this conversion work much better. Without fibrin, it converts only a limited amount of plasminogen. When alteplase is given into the systemic circulation at a pharmacologic concentration, it binds to fibrin in a thrombus and converts the plasminogen trapped there to plasmin. This starts fibrinolysis locally, with limited proteolysis in the rest of the body.
Pharmacodynamics: After a 100 mg dose of Alteplase, circulating fibrinogen falls by 16% to 36%. In one controlled trial, patients received Alteplase at 1.25 mg/kg body weight over 3 hours. In 8 of 73 of them (11%), fibrinogen dropped below 100 mg/dL.
Pharmacokinetics: In patients with acute myocardial infarction (AMI), alteplase clears quickly from the plasma, with an initial half-life of less than 5 minutes. The dominant initial plasma half-life is the same for the 3-hour regimen and the accelerated regimen in AMI. Plasma clearance of alteplase is 380 to 570 mL/min, and the liver does most of this work. The initial volume of distribution is close to the plasma volume.
Pregnancy & Breastfeeding
Alteplase is Pregnancy Category C. In rabbits given alteplase by intravenous injection, it killed the embryo at doses of about two times (3 mg/kg) the human dose for AMI. At 0.65 times (1 mg/kg) the human dose, pregnant rats and rabbits dosed during the period of organogenesis showed no harm to the mother or the fetus. There are no adequate and well-controlled studies in pregnant women.
It is not known whether alteplase is excreted in human milk. Many drugs are excreted in human milk.
⚠️ Talk to your doctor before taking any medicine during pregnancy or while breastfeeding.
Dosage Reference
⚠️ Reference ranges from official sources only. Consult your doctor for personalized dosing.