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Generic Name: alteplase (AL te plase)
Brand Name: Activase, Cathflo Activase

What is alteplase?

Alteplase is a thrombolytic (THROM-bo-LIT-ik) drug, sometimes called a "clot-busting" drug. It helps your body produce a substance that dissolves unwanted blood clots.

Alteplase is used to treat a stroke caused by a blood clot or other obstruction in a blood vessel. Alteplase is also used to prevent death from a heart attack (acute myocardial infarction).

Alteplase is also used to treat a blood clot in the lung (pulmonary embolism).

Alteplase is also used to dissolve blood clots that have formed in or around a catheter placed inside a blood vessel. This improve the flow of medicines injected in through the catheter, or blood drawn out through the catheter.

Alteplase may also be used for purposes not listed in this medication guide.

Important Information

Alteplase increases your risk of severe or fatal bleeding, especially from a surgical incision, or from the skin where a needle was inserted. Seek emergency help if you have any bleeding that will not stop.

Before taking this medicine

You should not be treated with alteplase if you are allergic to it, or if you have:

  • active bleeding inside your body;

  • a brain tumor or aneurysm (dilated blood vessel);

  • a history of head injury or surgery on your brain or spinal cord within the past 3 months; or

  • severe or uncontrolled high blood pressure;

  • a bleeding or blood clotting disorder such as hemophilia;

  • bleeding inside your brain (if you are receiving alteplase to treat a stroke); or

  • a recent history of stroke (if you are receiving alteplase for pulmonary embolism).

If possible before you receive alteplase, tell your doctor if you have ever had:

  • any type of stroke;

  • bleeding in your brain, stomach, intestines, or urinary tract;

  • high blood pressure;

  • heart problems;

  • an infection of the lining of your heart (also called bacterial endocarditis);

  • a serious injury or major surgery;

  • severe bruising or infection around a vein where an IV was placed;

  • an organ biopsy;

  • eye problems caused by diabetes;

  • liver or kidney disease; or

  • if you are pregnant or breastfeeding.

In an emergency situation it may not be possible to tell your caregivers if you are pregnant or breast-feeding. Make sure any doctor caring for your pregnancy or your baby knows you have received this medicine.

How is alteplase given?

Alteplase is injected into a vein through an IV. A healthcare provider will give you this injection.

Alteplase is usually given within 3 hours after the first signs of stroke or heart attack symptoms. Your breathing, blood pressure, oxygen levels, and other vital signs will be watched closely.

You will also be watched closely for several hours after receiving alteplase, to make sure you do not have an allergic reaction to the medication.

When used to clear blood clots from a catheter, alteplase is given in 1 or 2 doses. After the first dose, a small amount of blood is withdrawn through the catheter to make sure it is cleared of blood clots. If blood cannot be easily withdrawn 2 hours after the first dose of alteplase, a second dose may be given.

After treatment with alteplase, your doctor may prescribe a blood thinner or other medication to help prevent future blood clots. Carefully follow all dosing instructions. These medications can make it easier for you to bleed, even from a minor injury.

What happens if I miss a dose?

Because you will receive alteplase in a clinical setting, you are not likely to miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid after receiving alteplase?

Ask your doctor before taking aspirin or ibuprofen (Motrin, Advil) shortly after you have received alteplase. These medications can increase your risk of bleeding.

Avoid activities that may increase your risk of bleeding or injury. Use extra care to prevent bleeding while shaving or brushing your teeth.

Alteplase side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Alteplase increases your risk of bleeding, which can be severe or fatal. Call your doctor or seek emergency medical attention if you have bleeding that will not stop. Bleeding may occur from a surgical incision, or from the skin where a needle was inserted during a blood test or while receiving injectable medication. You may also have bleeding on the inside of your body, such as in your stomach or intestines, kidneys or bladder, brain, or within the muscles.

Call your doctor or get emergency medical help if you have signs of bleeding, such as:

  • sudden headache, feeling very weak or dizzy;

  • bleeding gums, nosebleeds;

  • easy bruising;

  • bleeding from a wound, incision, catheter, or needle injection;

  • bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds;

  • red or pink urine;

  • heavy menstrual periods or abnormal vaginal bleeding; or

  • sudden numbness or weakness (especially on one side of the body), slurred speech, problems with vision or balance.

Also call your doctor at once if you have:

  • chest pain or heavy feeling, pain spreading to the jaw or shoulder, nausea, sweating, general ill feeling;

  • swelling, rapid weight gain, little or no urination;

  • severe stomach pain, nausea, and vomiting;

  • darkening or purple discoloration of your fingers or toes;

  • very slow heartbeats, shortness of breath, feeling light-headed;

  • sudden severe back pain, muscle weakness, numbness or loss of feeling in your arms or legs;

  • increased blood pressure--severe headache, blurred vision, pounding in your neck or ears, anxiety, nosebleed; or

  • pancreatitis--severe pain in your upper stomach spreading to your back, nausea and vomiting, fast heart rate.

Bleeding is the most common side effect of alteplase.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Side Effects (complete list)

Alteplase dosing information

Usual Adult Dose for Myocardial Infarction:

For accelerated infusion method:
Over 67 kg: 100 mg administered as a 15 mg IV bolus followed by 50 mg infused over the next 30 minutes and then 35 mg infused over the next 60 minutes.
67 or less kg: 15 mg IV bolus, followed by 0.75 mg/kg (not to exceed 50 mg) infused over the next 30 minutes and then 0.5 mg/kg (not to exceed 35 mg) infused over the next 60 minutes.

For 3 hour infusion method:
Over 65 kg: 100 mg administered as 60 mg IV in the first hour (with 6 to 10 mg of it given as an IV bolus over 1 to 2 minutes), followed by 20 mg/hour IV during hours 2 and 3.
Less than 65 kg: 1.25 mg/kg administered as 0.75 mg/kg IV in the first hour (with 6 to 10 mg of it given as an IV bolus over 1 to 2 minutes), followed by 0.25 mg/kg/hour during hours 2 and 3. Heparin is usually given during and following administration of alteplase. Aspirin and/or dipyridamole have been given during and/or following heparin treatment.

Usual Adult Dose for Pulmonary Embolism:

50 mg/hour IV over 2 hours for a total dose of 100 mg. Heparin is usually started near the end or immediately following this infusion when partial thromboplastin time or thrombin time falls to twice the normal value or less.

Usual Adult Dose for Ischemic Stroke:

0.9 mg/kg (up to 90 mg) IV over 60 minutes with 10% of the total dose administered as an initial IV bolus over the first minute.

Usual Adult Dose for Thrombotic/Thromboembolic Disorder:

Occluded central venous catheter:
Manufacturer's recommendations (CathFlo Activase): Patients 30 or more kg: 2 mg in 2 mL; may instill second dose if catheter remains occluded after 2 hour dwell time. A recent study using escalating doses of 0.5 mg, 1 mg, and 2 mg (60 minute dwell time) found that 86.2% of catheters were cleared with the 0.5 mg dose.

Usual Pediatric Dose for Thrombotic/Thromboembolic Disorder:

Occluded IV catheter: Infuse in to catheter, do not infuse in to patient: Dose listed is per lumen; for multilumen catheters, treat one lumen at a time; dose should always be aspirated out of catheter after dwell.
Manufacturer's recommendations (CathFlo Activase):
Central venous catheter: post natal age 14 days or older: Use a 1 mg/mL concentration; instill a volume equal to 110% of the internal lumen volume of the catheter; do not exceed 2 mg in 2 mL; leave in lumen for up to 2 hours, then aspirate out of catheter; may instill a second dose if catheter remains occluded after 2 hour dwell time.
Alternative dosing:
Central venous catheter: 0.5 mg diluted in NS to a volume equal to the internal volume of the lumen; instill in each lumen over 1-2 minutes; leave in lumen for 1 to 2 hours, then aspirate out of catheter; flush catheter with NS.
Central venous catheter: 0.25 to 0.5 mg/mL solution; instill a volume to fill the catheter; leave in lumen for up to 2 hours, then aspirate out of catheter.

What other drugs will affect alteplase?

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • any medication used to treat or prevent blood clots;

  • a blood thinner (heparin, warfarin, Coumadin, Jantoven); or

  • NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others.

This list is not complete. Other drugs may interact with alteplase, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your doctor or pharmacist can provide more information about alteplase.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 2.01.

Last reviewed: November 28, 2017
Date modified: January 03, 2018