Trastuzumab Injection: Uses, Dosage, Side Effects, Precautions and Alternates

Quick overview

Trastuzumab Injection, generically called trastuzumab, is a monoclonal antibody used to treat certain HER2-overexpressing breast and stomach cancers. It is given by a doctor or nurse in a hospital or clinic, either as a slow infusion into a vein or as an injection under the skin of the thigh. It works by attaching to the HER2 protein on cancer cells to stop their growth and help the immune system destroy them. Treatment requires monitoring for heart problems, infusion reactions, and other effects.

What is Trastuzumab Injection

Trastuzumab is a targeted (biological) cancer therapy given by injection. It is a monoclonal antibody used to treat certain breast and stomach cancers that have extra amounts of a protein called HER2 on their surface.

Trastuzumab Injection uses

• Treats HER2-overexpressing breast cancer, including cancer that is new or has spread (metastatic)
• Treats HER2-overexpressing metastatic stomach and gastroesophageal (stomach and esophagus) cancer, usually combined with other chemotherapy drugs
• Can be used as treatment for primary breast cancer before surgery (to shrink the tumor) or after surgery (to reduce the chance it returns or spreads)
• Used to treat breast cancer that has come back locally, spread to nearby tissue, or spread to other parts of the body

Benefits of Trastuzumab Injection

• Slows or stops the growth and spread of HER2-positive cancer cells
• May shrink a large breast cancer before surgery
• Can reduce the likelihood of breast cancer returning or spreading after surgery
• Helps the body's immune system destroy breast cancer cells

How Trastuzumab Injection works

Trastuzumab attaches to the HER2 protein on cancer cells so the cells are no longer triggered to grow. It also helps the immune system destroy the cancer cells. It only works in cancers that make extra amounts of the HER2 protein.

Trastuzumab Injection dosage

This medicine is given by a doctor or nurse in a hospital or clinic—it is not taken at home. It is given slowly into a vein, with the needle staying in place for an extended period so the drug can be infused gradually. It can also be given as an injection under the skin of the thigh, alternating between the right and left thigh. You may need to stay at the hospital for a few hours after your first dose to make sure you feel well before going home. If you are having trastuzumab with another drug called pertuzumab, they may be combined into a single injection.

Keep all your scheduled appointments; if you must miss one, call your care team right away for instructions, since delaying treatment may require restarting with a loading dose. Continue your normal diet unless your doctor tells you otherwise.

Available forms and strengths

• Injection

Side effects of Trastuzumab Injection

Common

• Diarrhea or constipation
• Stomach pain or heartburn
• Loss of appetite
• Back, bone, joint, or muscle pain
• Trouble sleeping
• Hot flashes
• Numbness, burning, or tingling in arms, hands, feet, or legs
• Changes in nail appearance
• Acne
• Headache
• Dizziness
• Nausea or vomiting
• Skin rash
• Sore throat
• Stuffy or runny nose
• Unusual tiredness or weakness
• Fever or chills

Serious

• Signs of a serious heart problem: cough, shortness of breath, swelling of arms, hands, feet, ankles or lower legs, rapid weight gain, dizziness, loss of consciousness, or fast/irregular/pounding heartbeat
• Infusion reactions: fever, chills, nausea, vomiting, pain, headache, dizziness, weakness, rash, hives, itching, tightening of the throat, or difficulty breathing or swallowing
• Signs of infection: sore throat, fever, chills, pain or difficulty urinating
• Unusual bruising or bleeding, nosebleeds, pale skin, excessive tiredness
• Signs of a serious reaction: nausea, vomiting, loss of appetite, fatigue, rapid heartbeat, dark urine, decreased urine, stomach pain, seizures, hallucinations, muscle cramps and spasms
• Lung or breathing problems: changes in breathing, chest tightness, difficulty breathing
• Blood clots: pain, redness, heat and swelling of an arm or leg; shortness of breath; chest pain or tightness; coughing up blood

Warnings and precautions

• This medicine may cause serious or life-threatening heart problems. Your doctor will test your heart before and during treatment. Call your doctor right away if you have cough, shortness of breath, swelling of the limbs, rapid weight gain, dizziness, loss of consciousness, or an irregular heartbeat.
• This medicine may cause serious or life-threatening reactions during the infusion or up to 24 hours afterward, and may cause severe lung damage.
• This medicine can temporarily lower your white blood cell count, raising your risk of infection.
• There is a small risk of developing blood clots, which can be life-threatening but are treatable if reported early.
• Trastuzumab can harm an unborn baby. You should not become pregnant during treatment. You may need a pregnancy test before starting, and should use effective birth control during treatment and for 7 months after your last dose. Tell your doctor right away if you think you are pregnant.
• It is not known for certain whether this medicine is safe during breastfeeding, so the potential benefits must be weighed against the potential risks. One source advises not breastfeeding during treatment and for 7 months after stopping.
• Check for heart problems before and during treatment.
• Avoid during pregnancy unless specifically prescribed. Treatment should be given under specialist supervision.
• Discuss the use of alcohol with this medicine with your healthcare professional, as interactions may occur.
• Monitor for infusion-related reactions when driving.

Storage

• Store at 2–8°C.
• Do not freeze.
• Protect from light.
• Keep in the original carton.

When to see a doctor

• Call your doctor immediately if you have cough, shortness of breath, swelling of your arms, hands, feet, ankles or lower legs, rapid weight gain, dizziness, loss of consciousness, or a fast, irregular, or pounding heartbeat.
• Tell your doctor immediately if you have fever, chills, nausea, vomiting, pain, headache, dizziness, weakness, rash, hives, itching, tightening of the throat, or difficulty breathing or swallowing.
• Contact your doctor right away if you have chest pain, increased coughing, trouble breathing, sudden difficulty breathing at night, rapid weight gain, or abnormal swelling in your ankles or legs, as these may be signs of a serious heart problem.
• Contact your local emergency department, GP, or treatment team straight away if you notice pain, redness, heat, or swelling of an arm or leg; shortness of breath; chest pain or tightness; or an unexplained cough or coughing up blood, as these may be signs of a blood clot.
• If you think you may be pregnant during treatment, stop trastuzumab and tell your specialist as soon as possible.

Alternatives

• Pertuzumab
• Lapatinib
• Tucatinib