Trastuzumab may lead to serious heart problems, including heart failure. The risk of heart problems is increased if you also use an anthracycline (e.g., doxorubicin). Your doctor may need to stop this medication if heart problems occur.

Trastuzumab use may sometimes result in a serious reaction to the IV infusion with serious lung problems. If these problems occur, they usually happen while the drug is being given or within 24 hours of the dose. If you have trouble breathing or severe dizziness/fainting, tell your doctor or pharmacist immediately because your IV infusion may need to be stopped.

See also Side Effects section.

Trastuzumab is used alone or with other medications to treat certain types of breast cancer (tumors that produce more than the normal amount of a certain substance called HER2 protein).

This medication is called a monoclonal antibody. It works by attaching to the HER2 cancer cells and blocking them from dividing and growing. It may also destroy the cancer cells or signal the body (immune system) to destroy the cancer cells.

This medication will be given by a health care professional. It is mixed in a solution and given slowly by vein (IV), usually once a week or as directed by your doctor. Your first infusion will be given over at least 90 minutes.

Do not mix with IV fluids that contain dextrose. When mixed with IV fluids, this product will be colorless or clear yellow. Check this product visually for particles or discoloration before use. If either is present, do not use the liquid. Do not shake the IV liquid.

The dose, the speed of your injection, and the length of time you receive trastuzumab depends on your body weight, condition, other treatments, and response to trastuzumab treatment.

To get the most benefit from this medication, do not miss any doses. To help you remember, mark the days on the calendar when you need to receive the medication.

Your doctor may prescribe other medications (e.g., acetaminophen, diphenhydramine) for you to take before the start of your treatment to help prevent serious side effects.

Diarrhea, redness/irritation at injection (IV) site, muscle/joint/back pain, stomach/abdominal pain, trouble sleeping, nausea, vomiting, and loss of appetite may occur. Nausea and vomiting can be severe. In some cases, your doctor may prescribe medication to prevent or relieve nausea and vomiting. Eating several small meals, not eating before treatment, or limiting activity may help lessen some of these effects. If these effects persist or worsen, tell your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these unlikely but serious side effects occur: bone pain, increased coughing, swelling of the hands/ankles/feet, trouble breathing, unusual tiredness, severe headache, severe dizziness, tingling/numbness (e.g., in the hands, feet, leg), mental/mood changes, fast/pounding heartbeat.

Seek immediate medical attention if any of these rare but very serious side effects occur: weakness on one side of the body, slurred speech, vision changes, confusion.

This medication can lower the body's ability to fight an infection. Tell your doctor promptly if you develop any signs of an infection such as fever, chills, or persistent sore throat.

This medication can sometimes cause a serious infusion (IV) reaction. Immediately tell your doctor of the following side effects that occur while this drug is being given or within 24 hours after your treatment is finished, such as chills, fever, flushing, nausea, headache, dizziness, fainting, rash, and weakness. (See also Warning section.)

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before using trastuzumab, tell your doctor or pharmacist if you are allergic to it; or to other mouse protein medications; or to benzyl alcohol; or if you have any other allergies.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: previous cancer treatments (including radiation therapy to the chest), current infection, virus infection with returning symptoms (e.g., herpes, shingles), heart disease, high blood pressure, lung problems, previous severe reaction to monoclonal antibody treatment.

Do not have immunizations/vaccinations without the consent of your doctor, and avoid contact with people who have recently received oral polio vaccine or flu vaccine inhaled through the nose.

Wash your hands well to prevent the spread of infections.

To lower your risk of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.

This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

Caution is advised when using this drug in the elderly because they may be at greater risk for heart problems (e.g., heart failure).

This medication is not recommended during pregnancy because of the possible risk of harm to an unborn baby. Trastuzumab should only be used during pregnancy if the benefits outweigh these risks. Use 2 effective forms of birth control (e.g., condoms and birth control pills/patch/ring) while using this medication and for 6 month after treatment has stopped. Consult your doctor for more details and to discuss reliable forms of birth control.

It is not known whether this drug passes into breast milk. Because of the possible risk to the infant, breast-feeding is not recommended while using this drug or for 6 months after the last dose.

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: current or previous use of other anti-cancer drugs (e.g., doxorubicin, daunorubicin, cyclophosphamide), drugs for high blood pressure, recent or planned immunizations (e.g., polio vaccine taken by mouth, measles vaccine), drugs that affect the immune system (e.g., cyclosporine, corticosteroids such as prednisone).

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center.

Do not share this medication with others.

Laboratory and/or medical tests (e.g., heart exams) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.

It is very important that you do not miss any doses. However, if you miss a dose, contact your doctor immediately to establish a new dosing schedule.

Store vials in a refrigerator between 36-46 degrees F (2-8 degrees C) away from light and moisture. Do not use this product past the expiration date stamped on the vial.

Consult your pharmacist for directions on how to store the mixed and diluted product.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

MEDICAL ALERT: Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-800-854-1166 (USA) or 1-800-668-1507 (Canada).

Information last revised July 2009 Copyright(c) 2009 First DataBank, Inc.