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What common side effects occur with Perjeta?

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on Aug 22, 2023.

Official answer


While not everyone will experience serious side effects, side effects can be common with Perjeta (generic name: pertuzumab) Side effects can vary based on the different treatment regimens you may receive, but some of the most common Perjeta side effects include:

  • Constipation
  • Diarrhea
  • Damage to the nerves (numbness, tingling, pain in hands/feet)
  • Feeling tired (fatigue)
  • Hair loss (alopecia)Headache
  • Low levels of red blood cells
  • Low levels of white blood cell (with or without a fever)
  • Low platelet counts (platelets are needed for blood clotting)
  • Mouth blisters or sores
  • Muscle pain
  • Nausea, vomiting
  • Rash
  • Weakness

You may need to stop your treatment early if the side effects are difficult to manage or the cancer comes back sooner. Perjeta is given with a drug known as Herceptin, also used for breast cancer treatment. If your doctor delays or stops your Herceptin treatment, then Perjeta should also be delayed or stopped.

Serious heart side effects can occur with Perjeta treatment. Your doctor will monitor your heart function before and during treatment. Contact your doctor immediately for any of the following:

  • new onset or worsening shortness of breath
  • cough
  • swelling of the ankles/legs
  • swelling of the face
  • palpitations
  • weight gain of more than 5 pounds in 24 hours
  • dizziness or loss of consciousness.

If you think you may be pregnant, you should contact your health care provider immediately. Perjeta can cause the death of an unborn baby and birth defects.

  • Talk to your doctor about the need for effective birth control. Birth control should be used while receiving Perjeta and for 7 months after your last dose of Perjeta. If you are a mother who is breastfeeding, you should talk with your doctor about either stopping breastfeeding or stopping Perjeta.

Perjeta has also been associated with serious infusion reactions and allergic reactions (hypersensitivity reactions or anaphylaxis), some of which have been fatal. Do not use pertuzumab if you are allergic to it or to any of its ingredients.

These are not all the possible side effects with Perjeta. Talk to your doctor and health care team immediately if you have any questions or are concerned about any side effects.

Learn More: Side Effects with Perjeta (in more detail)

Bottom Line

  • Some of the most common side effects with Perjeta include: diarrhea, alopecia, neutropenia, nausea, vomiting, fatigue, rash, low red or white blood cells, and nerve damage. Other side effects can also occur.
  • Your doctor will monitor you for side effects while you are receiving Perjeta, and may delay or stop treatment if needed based on the severity of the effects.
  • These are not all the possible side effects with Perjeta. Talk to your doctor and health care team immediately if you have any questions or concerns about side effects or treatment.

This is not all the information you need to know about Perjeta for safe and effective use. Review the full Perjeta information here and discuss this information with your doctor or other health care provider.

  • Perjeta Dosing and Administration Guide. Genentech (online). June 2019. Accessed Sept. 1, 2020 at
  • Perjeta (pertuzumab) Product Information. Genentech, Inc. South San Francisco, CA. Jan. 2020. Accessed Sept. 1, 2020 at
  • Perjeta (pertuzumab). Genentech, Inc. South San Francisco, CA. 2019. Accessed Sept. 1, 2020 at

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