Trastuzumab: functions, dosage, side effects, how to use it

What medicine is Trastuzumab?

What is trastuzumab for?

Trastuzumab is a drug that is used alone or with other medicines to treat certain types of breast cancer. This drug is also used with other medicines to treat certain types of stomach cancer. The types of cancer trastuzumab can treat are tumors that overproduce the substance HER2 protein.

These drugs are called monoclonal antibodies. This drug works by attaching to HER2 cancer cells and stopping them from dividing and growing. These drugs may also destroy cancer cells or signal the body (immune system) to destroy cancer cells.

How do I use trastuzumab?

Trastuzumab is different from trastuzumab emtansine or ado-trastuzumab emtansine. Do not replace trastuzumab with trastuzumab emtansine or ado-trastuzumab emtansine.

This medicine will be given by a health care provider. Given by slow infusion, usually once a week for breast cancer or once every three weeks for stomach cancer or as directed by your doctor. Your first infusion can be given for at least 90 minutes.

The dose, injection speed, and how long you receive trastuzumab depend on your weight, condition, other medications and your response to trastuzumab treatment.

To achieve the desired results from this medicine, do not skip your dose. To help you remember, mark the days you should take your medication on a calendar.

Your doctor may prescribe other medicines (for example: acetaminophen, diphenhydramine) for you to use before starting treatment to help prevent serious side effects.

How do I store trastuzumab?

This medication is best stored at room temperature, away from direct light and damp places. Don't keep it in the bathroom. Don't freeze it. Other brands of this drug may have different storage rules. Observe the storage instructions on the product package or ask your pharmacist. Keep all medicines away from children and pets.

Do not flush medicines down the toilet or down the drain unless instructed to do so. Discard this product when it has expired or when it is no longer needed. Consult your pharmacist or local waste disposal company about how to safely dispose of your product.

Trastuzumab dosage

The information provided is not a substitute for medical advice. ALWAYS consult your doctor or pharmacist before starting treatment.

What is the dose of trastuzumab for adults?

Dosage for Breast Cancer in Adults

metastatic breast cancer:

initial dose: 4 mg / kg infusion over 90 minutes, with or without paclitaxel

maintenance dose: 2 mg / kg infusion for 30 minutes once a week.

Duration of therapy: until disease progression occurs

Dosage for Breast Cancer in Adults - Advanced Therapy

Breast cancer follow-up treatment:

-when given or followed by paclitaxel, docetaxel, or docetaxel / carboplatin: Initial dose: 4 mg / kg infusion over 90 minutes, then 2 mg / kg IV for 30 minutes each week for 12 weeks (paclitaxel or docetaxel) or 18 weeks (docetaxel / carboplatin)

Maintenance dose: 6 mg / kg infusion for 30 to 90 minutes once every three weeks, starting a week after completing the weekly dose.

When used as a single treatment within 3 weeks after a multi-modal anthracycline-based sequence:

Initial dose: 8 mg / kg infusion for 90 minutes

Maintenance dose: 6 mg / kg infusion for 30 to 90 minutes once every three weeks

Duration of therapy: 52 weeks

Dosage for Esophageal Carcinoma in Adults:

Metastatic gastric cancer:

Initial dose: 8 mg / kg IV for 90 minutes

Maintenance dose: 6 mg / kg IV for 30 to 90 minutes once every three weeks

Duration of therapy: until disease progression occurs

Dosage for Stomach Cancer in Adults:

Metastatic gastric cancer:

Initial dose: 8 mg / kg IV for 90 minutes

Maintenance dose: 6 mg / kg IV for 30 to 90 minutes once every three weeks

Duration of therapy: until disease progression occurs

What is the dose of trastuzumab for children?

The dosage for children (less than 18 years of age) has not been established. Consult your doctor for more information.

In what dosage is trastuzumab available?

Powder for a 40 mg solution

Trastuzumab side effects

What side effects can trastuzumab experience?

Some people who receive trastuzumab injection experience reactions to the infusion (when the drug is injected into a vein). Tell your doctor or nurse right away if you experience dizziness, nausea, lightheadedness, weakness, itching, or shortness of breath during injection.

Seek emergency help immediately if you experience any of the following signs of an allergic reaction: rash; difficulty breathing; swelling of the face, lips, tongue, or throat.

Call your doctor right away if you experience the following serious side effects:

• a racing heart
• shortness of breath (despite not doing strenuous activities), swelling, rapid weight gain; coughing or wheezing
• fever, chills, body aches, flu symptoms, canker sores in the mouth and throat
• pale skin, difficulty concentrating, bruising easily, unusual bleeding (nose, mouth, vagina, or rectum), purple or red spots on the skin

Possible minor side effects:

• nausea, vomiting, diarrhea, weight loss
• headache, muscle aches
• sleep problems (insomnia)
• flu symptoms such as stuffy nose, sinus pain, sneezing, sore throat
• mild rash
• changes in the sense of taste
• tired feeling

Not everyone experiences the above side effects. There may be some side effects not listed above. If you have concerns about certain side effects, consult your doctor or pharmacist.

Trastuzumab Drug Warnings and Cautions

What should be known before using trastuzumab?

When deciding which drug to use, the risks and benefits of using the drug must be considered. This is a decision made by you and your doctor. The following should be considered for this drug:

Allergy

Tell your doctor if you have had an allergic or unusual reaction when using this medicine or other medicines. Tell your health care provider if you have any other allergies such as food allergies, food coloring, preservatives, or animals. For non-prescription products, read carefully the composition written on the packaging.

Children

Research related to the relationship of age with the effects of Trastuzumab has not been conducted in children. Security and effectiveness have not been established.

Elderly

No information is available on the relationship between age and the effects of Trastuzumab in elderly patients. However, elderly patients have a higher risk of developing problems due to advancing age which may require adjusting the dose of Trastuzumab.

Is trastuzumab safe for pregnant and lactating women?

There are no adequate studies regarding the risks of using this drug in pregnant or breastfeeding women. Always consult your doctor to weigh the potential benefits and risks before using this medication. This drug is included in the risk of pregnancy category D according to the US Food and Drug Administration (FDA).

The following references the pregnancy risk categories according to the FDA:

A = Not at risk

B = No risk in several studies

C = May be risky

D = There is positive evidence of risk

X = Contraindicated

N = Unknown

Trastuzumab Drug Interactions

What medicines may interact with trastuzumab?

Drug interactions can change how the drugs work or increase your risk for serious side effects. This document does not include all drug interactions that can occur. Keep a list of the products you use (including prescription / nonprescription medicines and herbal products) and tell your doctor and pharmacist. Do not start, stop, or change the dose of any medication without your doctor's knowledge.

Use of this medication with any of the following medicines is not usually recommended, but in some cases it may be necessary. If the two drugs are prescribed together, the doctor may change the dose or how often one or both drugs are used.

• Aclarubicin
• Cyclophosphamide
• Daunorubicin
• Daunorubicin Citrate Liposome
• Doxorubicin
• Doxorubicin Hydrochloride Liposome
• Epirubicin
• Idarubicin
• Pirarubicin

Using this medication with any of the following medicines may increase your risk of certain side effects, but using both drugs may be the best treatment for you. If the two drugs are prescribed together, the doctor may change the dose or how often one or both drugs are used.

• Warfarin

Can food or alcohol interact with trastuzumab?

Certain drugs should not be used with meals or when eating certain foods because drug interactions can occur. Consuming alcohol or tobacco with certain drugs can also cause interactions to occur. Discuss your use of drugs with food, alcohol, or tobacco with your health care provider.

What health conditions can interact with trastuzumab?

The presence of other health problems can affect the use of this drug. Tell your doctor if you have other health problems, specifically:

• alcohol poisoning
• underactive adrenal glands
• an underactive pituitary gland
• malnutrition
• weak physical condition
• other conditions that cause low blood sugar - patients with this condition have a higher chance of developing low blood sugar while using trastuzumab
• diabetic ketoacidosis (ketones in the blood)
• type 1 diabetes — should not be used in people with this condition
• fever
• infection
• operation
• trauma — this condition can cause temporary problems with blood sugar control and your doctor may temporarily treat you with insulin.
• heart disease - use with caution. Can make this condition worse
• kidney disorders
• liver disorders - blood levels of this drug can increase, risking serious problems

Trastuzumab overdose

What should I do in an emergency or overdose?

In case of an emergency or overdose, contact the local emergency services provider (112) or immediately to the nearest hospital emergency department.

What should I do if I miss a dose?

If you forget a dose of this medicine, take it as soon as possible. However, when it is nearing the time of the next dose, skip the missed dose and return to the usual dosing schedule. Don't double the dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.