Boxed warnings

This drug has boxed warnings about the risk of heart problems, infusion reaction, lung problems, and problems with fetal development. These are serious warnings from the Food and Drug Administration (FDA). A boxed warningTrusted Source alerts doctors and patients about drug effects that may be dangerous.

Heart problems. Taking Herceptin can cause heart problems, including heart failure. Heart problems are more likely in people who take Herceptin with anthracyclines (a group of chemotherapy drugs). Be sure to tell your doctor if you’ve ever had heart problems.

Your doctor will check your left ventricular ejection fraction (LVEF) before and during Herceptin treatment. (LVEF is a measurement of how well your heart pumps blood throughout your body.) If your LVEF decreases during Herceptin treatment, your doctor may pause your therapy. They’ll determine if you can continue treatment or if you’ll need to stop completely. If you have any of the following problems during or after a Herceptin dose, tell your doctor:

* feeling short of breath
* cough
* swelling of the legs or ankles
* swelling of the face
* racing heartbeat
* gaining more than 5 pounds in 24 hours
* feeling dizzy or fainting

Infusion reaction. Herceptin is given as an IV infusion by your doctor or another healthcare professional. The drug can cause severe infusion reactions that can lead to death in rare cases. Symptoms usually happen during or within 24 hours of your Herceptin infusion. They include:

* feeling short of breath
* extremely low blood pressure
* life threatening allergic reaction
* swelling under the skin due to an allergic reaction
* interstitial pneumonitis (scarring in your lungs)
* acute respiratory distress syndrome (a serious condition that causes fluid buildup in the lungs)

If you have a mild or moderate reaction during your Herceptin infusion, your doctor may slow down your infusion. This means you’ll get the same amount of the drug, but your infusion will take longer. If you have shortness of breath or extremely low blood pressure during your infusion, your doctor will likely pause the infusion. If you have a severe life threatening reaction, your doctor will typically stop your Herceptin treatment permanently.

Lung problems. Herceptin can cause lung problems such as shortness of breath and scarring in the lungs. It can also cause fluid buildup in the lungs or between the tissues that line the lungs. These lung problems are more likely to happen in people with lung disease or lung tumors. Typically, they occur during or within 24 hours of your Herceptin infusion.

If you have shortness of breath or other lung problems during your Herceptin infusion, your doctor will likely pause the infusion. If your symptoms are severe or life threatening, your doctor may stop your Herceptin treatment permanently.

Problems with fetal development. If taken during pregnancy, Herceptin can decrease the level of amniotic fluid in the uterus. This can cause serious problems with fetal development. It can even lead to fetal death in rare cases. Due to this risk, you should use effective birth control during Herceptin treatment. You should also use it for 7 months after your last dose.

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Herceptin (trastuzumab) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it to treat certain types of cancer that contain human epidermal growth factor receptor 2 (HER2). The drug is approved for use in adults.

Specifically, Herceptin is used to treat:

Herceptin is known as a HER2-targeted therapy. The FDA has approved several biosimilar forms of Herceptin: Herzuma, Kanjinti, Ogivri, Ontruzant, and Trazimera.

Herceptin comes as a powder in a single-dose vial. The powder is mixed with sterile water to form a solution that’s given as an IV infusion. Your doctor or another healthcare professional will give you your infusion.

For breast cancer, Herceptin is typically prescribed for 52 weeks. For metastatic cancers, Herceptin is given until it’s no longer effective for your condition.

Dosage summary

The following table summarizes Herceptin’s dosages. Your doctor will determine the dosage that’s best for you.

Herceptin useLoading dose (first infusion)Maintenance (long-term) infusion dosage
To treat HER2-positive breast cancer when used with or after treatment with paclitaxel or docetaxel4 milligrams per kilogram of body weight* (mg/kg) given over 90 minutes2 mg/kg given over 30 minutes, once per week for 12 weeks†
To treat HER2-positive breast cancer when used with or after treatment with docetaxel and carboplatin4 mg/kg given over 90 minutes2 mg/kg given over 30 minutes, once per week for 18 weeks†
To treat HER2-positive breast cancer after treatment with anthracycline drugs8 mg/kg given over 90 minutes6 mg/kg given over 30 to 90 minutes, once every 3 weeks
To treat HER2-positive metastatic breast cancer alone or with paclitaxel4 mg/kg given over 90 minutes2 mg/kg given over 30 minutes, once per week
To treat HER-2 positive metastatic gastric cancer8 mg/kg given over 90 minutes6 mg/kg given over 30 to 90 minutes, once every 3 weeks

* One kg is about 2.2 pounds (lb).
† One week after your last infusion, your doctor may give you 6 mg/kg over 30 to 90 minutes. This will likely be once every 3 weeks for 39 weeks.

For information about the dosage of Herceptin, including its strength and how the drug is given, keep reading. For a comprehensive look at Herceptin, see this article.

Below is information about Herceptin and its typical dosages for different types of cancer.

Herceptin form

Herceptin comes as a powder in a single-dose vial. The powder is mixed with sterile water to form a solution that’s given as an IV infusion. Your doctor or another healthcare professional will give you your infusion.

Herceptin strength

Herceptin comes in one strength: 150 milligrams (mg).

Typical dosages

Your Herceptin dosage will depend on the type of cancer you have. The dosage your doctor prescribes may change over time.

The following information describes dosages that are commonly prescribed or recommended. Your doctor will determine the best dosage to fit your needs.

Dosage for HER2-positive breast cancer

See below for specific dosages of Herceptin for HER2-positive breast cancer.

Herceptin dosage given with or after certain treatments

For this use, doctors may prescribe Herceptin with certain drugs. These include doxorubicin, cyclophosphamide, and either paclitaxel or docetaxel. If you have treatment with docetaxel, it may be with or without carboplatin. Your doctor may also prescribe Herceptin after you finish treatment with these drugs.

Typically, the loading dose (first infusion) of Herceptin is 4 milligrams per kilogram of body weight (mg/kg). (One kg is about 2.2 pounds [lb].) For example, if you weigh 69 kg (about 152 lb), your total dose would be 276 mg.

This first dose will be given as an IV infusion over 90 minutes. After that, you’ll typically receive a maintenance (long-term) dose of 2 mg/kg of Herceptin given over 30 minutes. You’ll receive this dose once per week for 12 to 18 weeks.

One week after your last infusion, your doctor may give you 6 mg/kg over 30 to 90 minutes. This will likely be once every 3 weeks for 39 weeks.

You and your doctor will decide if continuing weekly treatment or switching to treatment every 3 weeks is right for you. Regardless of your dosing schedule, you’ll likely take Herceptin for a total of 52 weeks.

Herceptin dosage after anthracycline treatment

For this use, your doctor may prescribe Herceptin after your cancer is treated with certain anthracycline drugs.

Your doctor will usually start Herceptin treatment within 3 weeks of your last anthracycline dose.

In this case, the loading dose of Herceptin will likely be 8 mg/kg given over 90 minutes. After that, you’ll receive a maintenance dose of 6 mg/kg given over 30 to 90 minutes. You’ll receive this dose once every 3 weeks over 52 weeks.

Dosage for HER2-positive metastatic breast cancer

To treat HER2-positive metastatic breast cancer, your doctor may prescribe Herceptin on its own or with paclitaxel.

Typically, the loading dose (first infusion) of Herceptin is 4 milligrams per kilogram of body weight (mg/kg). (One kg is about 2.2 pounds [lb].) For example, if you weigh 69 kg (about 152 lb), your total Herceptin dose would be 276 mg.

This first infusion is typically given over 90 minutes. After that, you’ll receive a maintenance (long-term) dose of 2 mg/kg given over 30 minutes. You’ll receive this dose once per week until Herceptin is no longer effective for your condition.

Dosage for HER-positive metastatic gastric cancer

For HER-positive metastatic gastric cancer, your doctor may prescribe Herceptin with other drugs. These include cisplatin and either Xeloda (capecitabine) or 5-fluorouracil.

Typically, the loading dose (first infusion) of Herceptin is 8 milligrams per kilogram of body weight (mg/kg). (One kg is about 2.2 pounds [lb].) For example, if you weigh 69 kg (about 152 lb), your total Herceptin dose would be 552 mg.

This first infusion is typically given over 90 minutes. After that, you’ll receive a maintenance (long-term) dose of 6 mg/kg given over 30 to 90 minutes. You’ll receive this once every 3 weeks until Herceptin is no longer effective for your condition.

Long-term treatment

Herceptin is meant to be given for 52 weeks or longer. This depends on your condition. If you and your doctor determine that Herceptin is safe and effective for you, you’ll likely take it long term.

Below are some frequently asked questions about Herceptin.

How often is Herceptin given? Will I get a Herceptin dose every 3 weeks?

How often you get Herceptin depends on the type of cancer you have. You may receive a Herceptin dose once per week or once every 3 weeks. Typically, you’ll receive a dose once every 3 weeks if you have:

If you have questions about how often you’ll be given Herceptin, talk with your doctor. You can also see the “Herceptin dosage” section above.

Is Herceptin prescribed with a loading dose?

Yes. Typically, Herceptin is prescribed with a loading dose. A loading dose is given at the beginning of treatment. And it usually has a higher amount of drug than the doses you’ll get later on. Your loading dose will depend on what type of cancer you have.

If you have questions about your Herceptin loading dose, talk with your doctor. You can also see the “Herceptin dosage” section above.

Does having obesity affect Herceptin’s dosing?

Yes. Having obesity (a body mass index of 30 or more) affects Herceptin’s dosing. This is because Herceptin’s dosing is based on how much you weigh. Also, the dose you receive may change over time if you gain or lose weight.

Herceptin is prescribed in milligrams per kilogram of body weight (mg/kg). (One kg is about 2.2 pounds [lb].) For example, if your dose is 4 mg/kg and you weigh:

  • 46 kg (about 101 lb), you would receive 184 mg of Herceptin
  • 90 kg (about 198 lb), you would receive 360 mg of Herceptin

If you have questions about your weight and Herceptin dosing, talk with your doctor.

The Herceptin dosage your doctor prescribes will depend on several factors. These include:

Other medical conditions you have can also affect your Herceptin dosage.

Herceptin comes as a powder in a single-dose vial. The powder is mixed with sterile water to form a solution that’s given as an IV infusion. (An IV infusion is an injection given over a period of time.) Your doctor or another healthcare professional will give you your infusion.

To get your infusion, you’ll visit your doctor’s office or clinic. The infusion typically lasts 30 to 90 minutes.

For more details about how Herceptin is given, talk with your doctor.

It’s important to stick to your Herceptin treatment schedule. If you miss an infusion appointment for your dose, call your doctor to reschedule as soon as possible. Typically, if you miss an infusion by:

  • one week or less, you may be able to get your usual maintenance (long-term) dose as soon as possible
  • more than one week, you may need another loading dose (first infusion)

In general, you’ll be able to continue your treatment schedule after getting the missed dose.

To help make sure you don’t miss an infusion appointment, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.

The dosages in this article are typical dosages provided by the drug’s manufacturer. If your doctor recommends Herceptin for you, they will prescribe the dosage that’s right for you. If you have questions about the dosage of Herceptin that’s right for you, talk with your doctor.

Besides learning about dosage, you may want other information about Herceptin. These additional articles might be helpful:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.