What should I know about side effects?

Learn How You May Feel During Treatment

Learn how you may feel during treatment

Throughout treatment, side effects may happen. That’s why you should know what the possible side effects of KEYTRUDA are and talk to your doctor immediately about what you can do to help manage them.

Why Is It Important to Know About Potential Side Effects?

Why is it important to know about potential side effects?

You may experience side effects at any time during your treatments or even after they have ended. That’s why it’s important to get to know what the side effects are. This can help you more easily recognize them if you start to feel any of the symptoms.

Side effects may occur while taking KEYTRUDA

During treatment with KEYTRUDA, side effects can occur and should be treated as early as possible. In clinical trials with KEYTRUDA, some patients stopped treatment due to side effects. Tell your doctor if you have any side effect that bothers you or that does not go away.

Serious side effects

KEYTRUDA is a medicine that may treat certain cancers by working with your immune system. KEYTRUDA can cause your immune system to attack normal organs and tissues in any area of your body and can affect the way they work. These problems can sometimes become severe or life-threatening and can lead to death. You can have more than one of these problems at the same time. These problems may happen anytime during treatment or even after your treatment has ended.

Call or see your health care provider right away if you develop any signs or symptoms of the following problems or if they get worse. These are not all of the signs and symptoms of immune system problems that can happen with KEYTRUDA:

Lung problems

  • Cough
  • Shortness of breath
  • Chest pain

Intestinal problems

  • Diarrhea (loose stools) or more frequent bowel movements than usual
  • Stools that are black, tarry, sticky, or have blood or mucus
  • Severe stomach-area (abdomen) pain or tenderness

Liver problems

  • Yellowing of your skin or the whites of your eyes
  • Severe nausea or vomiting
  • Pain on the right side of your stomach area (abdomen)
  • Dark urine (tea colored)
  • Bleeding or bruising more easily than normal

Kidney problems

  • Decrease in your amount of urine
  • Blood in your urine
  • Swelling of your ankles
  • Loss of appetite

Skin problems

  • Rash
  • Itching
  • Skin blistering or peeling
  • Painful sores or ulcers in your mouth or in your nose, throat, or genital area
  • Fever or flu-like symptoms
  • Swollen lymph nodes

Hormone gland problems

  • Headaches that will not go away or unusual headaches
  • Eye sensitivity to light
  • Eye problems
  • Rapid heartbeat
  • Increased sweating
  • Extreme tiredness
  • Weight gain or weight loss
  • Feeling more hungry or thirsty than usual
  • Urinating more often than usual
  • Hair loss
  • Feeling cold
  • Constipation
  • Your voice gets deeper
  • Dizziness or fainting
  • Changes in mood or behavior, such as decreased sex drive, irritability, or forgetfulness

Problems can also happen in other organs and tissues. These are not all of the signs and symptoms of immune system problems that can happen with KEYTRUDA. Call or see your health care provider right away for any new or worsening signs or symptoms, which may include:

  • Chest pain, irregular heartbeat, shortness of breath, swelling of ankles
  • Confusion, sleepiness, memory problems, changes in mood or behavior, stiff neck, balance problems, tingling or numbness of the arms or legs
  • Double vision, blurry vision, sensitivity to light, eye pain, changes in eyesight
  • Persistent or severe muscle pain or weakness, muscle cramps
  • Low red blood cells, bruising

Infusion reactions that can sometimes be severe or life‑threatening.

Signs and symptoms of infusion reactions may include:

  • Chills or shaking
  • Itching or rash
  • Flushing
  • Shortness of breath or wheezing
  • Dizziness
  • Feeling like passing out
  • Fever
  • Back pain

Rejection of a transplanted organ. Your health care provider should tell you what signs and symptoms you should report and they will monitor you, depending on the type of organ transplant that you have had.

Complications, including graft-versus-host-disease (GVHD), in people who have received a bone marrow (stem cell) transplant that uses donor stem cells (allogeneic). These complications can be serious and can lead to death. These complications may happen if you underwent transplantation either before or after being treated with KEYTRUDA. Your health care provider will monitor you for these complications.

Getting medical treatment right away may help keep these problems from becoming more serious. Your health care provider will check you for these problems during treatment with KEYTRUDA. They may treat you with corticosteroid or hormone replacement medicines. They may also need to delay or completely stop treatment with KEYTRUDA, if you have severe side effects.

Common side effects

Common side effects of KEYTRUDA when used alone include: feeling tired, pain, including pain in muscles, bones or joints and stomach-area (abdominal) pain, decreased appetite, itching, diarrhea, nausea, rash, fever, cough, shortness of breath, and constipation.

Side effects of KEYTRUDA when used alone that are more common in children than in adults include: fever, vomiting, upper respiratory tract infection, headache, and low levels of white blood cells and red blood cells (anemia).

Common side effects of KEYTRUDA when given with certain chemotherapy medicines include: feeling tired or weak, nausea, constipation, diarrhea, decreased appetite, rash, vomiting, cough, trouble breathing, fever, hair loss, inflammation of the nerves that may cause pain, weakness, and paralysis in the arms and legs, swelling of the lining of the mouth, nose, eyes, throat, intestines, or vagina, mouth sores, and headache.

Common side effects of KEYTRUDA when given with axitinib include: diarrhea, feeling tired or weak, high blood pressure, liver problems, low levels of thyroid hormone, decreased appetite, blisters or rash on the palms of your hands and soles of your feet, nausea, mouth sores or swelling of the lining of the mouth, nose, eyes, throat, intestines, or vagina, hoarseness, rash, cough, and constipation.

These are not all the possible side effects of KEYTRUDA. Talk to your health care provider for medical advice about side effects.

Write Down All Physical and Emotional Changes

Write down all physical and emotional changes

Even before you get your first infusion, write down how you feel physically and emotionally. This will help you recognize if you start to feel anything out of the ordinary. Keep these key things in mind:

  • Consider downloading an app to your phone by searching key phrases like “side effects tracker” or download and print the Symptom Tracker (PDF) to make tracking easy
  • Talk to your doctor about what you can expect from treatment
  • Write down how you are feeling early and often (before, during, after, and even in between infusions)
What Are Some Examples of What I Should Write Down?

What are some examples of what I should write down?

Use these suggestions as a starting point to writing down how you are feeling:

  • The date you’re feeling a symptom
  • What your symptom is and/or how you feel overall
  • What your energy level and/or mood is like
  • How your doctor suggests you can manage the symptom
When Should I Speak Up If I Feel Something New or Different?

When should I speak up if I feel something new or different?

You should speak up immediately if you feel something new or different.

Calling or talking to a member of your cancer care team may keep your side effects from getting more serious. It may also enable your doctor to help you manage any side effects with medication.

How Can I Manage Some Common Side Effects Myself?

How can I manage some common side effects myself?

Use these quick tips to help you manage some side effects at home. It’s important to tell your doctor about all side effects you have, even those you can manage at home.

Feeling tired (fatigue):

  • Take quick naps of 30 minutes or less for an energy boost
  • Ask others for help with difficult tasks

Mild diarrhea:

  • Drink plenty of water to keep yourself hydrated
  • Avoid dairy products, alcohol, caffeine, and spicy foods

Nausea:

  • Eat smaller meals more frequently
  • Drink clear liquids and ice-cold beverages
Read How One Patient Managed a Common Side Effect

Read how one patient managed a common side effect

Meet Jeff, a real patient taking KEYTRUDA, and learn how he and his doctor managed the tiredness he felt after infusions.

I found that just getting up and doing something really helped combat fatigue. That’s why you have to get up, get moving, and stay active.
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Hopefully you have a better understanding of what you should know about the side effects of KEYTRUDA. Now that you learned to write down how you are feeling, when you should speak up, and some quick tips to manage common side effects, you’re ready to move onto the next section.

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FDA-Approved Indications

KEYTRUDA is a prescription medicine used to treat:

  • a kind of skin cancer called melanoma.
    • It may be used when your melanoma has spread or cannot be removed by surgery (advanced melanoma), or
    • It may be used to help prevent melanoma from coming back after it and lymph nodes that contain cancer have been removed by surgery.
  • a kind of lung cancer called non–small cell lung cancer (NSCLC).
    • It may be used with the chemotherapy medicines pemetrexed and a platinum as your first treatment when your lung cancer has spread (advanced NSCLC) and is a type called “nonsquamousand your tumor does not have an abnormal “EGFR” or “ALK” gene.
    • It may be used with the chemotherapy medicines carboplatin and either paclitaxel or paclitaxel protein-bound as your first treatment when your lung cancer has spread (advanced NSCLC), and is a type called “squamous.”
    • It may be used alone as your first treatment when your lung cancer has not spread outside your chest (stage III) and you cannot have surgery or chemotherapy with radiation, or your NSCLC has spread to other areas of your body (advanced NSCLC), and your tumor tests positive for “PD-L1and does not have an abnormal “EGFR” or “ALK” gene.
    • It may also be used alone for advanced NSCLC if you have tried chemotherapy that contains platinum and it did not work or is no longer working and, your tumor tests positive for “PD-L1and if your tumor has an abnormal “EGFR” or “ALK” gene, you have also received an “EGFR” or “ALK” inhibitor medicine that did not work or is no longer working.
  • a kind of cancer called head and neck squamous cell cancer (HNSCC).
    • It may be used with the chemotherapy medicines fluorouracil and a platinum as your first treatment when your head and neck cancer has spread or returned and cannot be removed by surgery.
    • It may be used alone as your first treatment when your head and neck cancer has spread or returned and cannot be removed by surgery, and your tumor tests positive for “PD-L1.”
    • It may be used alone when your head and neck cancer has spread or returned, and you have received chemotherapy that contains platinum and it did not work or is no longer working.
  • a kind of cancer called classical Hodgkin lymphoma (cHL). It may be used
    • in adults when:
      • your cHL has returned or
      • you have tried a treatment and it did not work, or
    • in children when:
      • you have tried a treatment and it did not work, or
      • your cHL has returned after you received 2 or more types of treatment.
  • a kind of cancer called primary mediastinal B-cell lymphoma (PMBCL). It may be used in adults and children when you have tried a treatment and it did not work, or your PMBCL has returned after you received 2 or more types of treatment.
  • a kind of bladder and urinary tract cancer called urothelial carcinoma.
    • It may be used when your cancer has not spread to nearby tissue in the bladder, but is at high-risk for spreading (high-risk, non-muscle invasive bladder cancer [NMIBC]) and when your tumor is a type called “carcinoma in situ” (CIS), and you have tried treatment with Bacillus Calmette-Guerin (BCG) and it did not work, and you are not able to or have decided not to have surgery to remove your bladder.
    • It may be used when your bladder or urinary tract cancer has spread or cannot be removed by surgery (advanced urothelial cancer), and you are not able to receive chemotherapy that contains a medicine called cisplatin, and your tumor tests positive for “PD-L1,” or you are not able to receive a medicine called cisplatin or carboplatin.
      This use is approved based on how many patients responded to treatment and how long they responded. Studies are ongoing to provide additional information about clinical benefit.
    • It may be used when your bladder or urinary tract cancer has spread or cannot be removed by surgery (advanced urothelial cancer) and you have received chemotherapy that contains platinum, and it did not work or is no longer working.
  • a kind of cancer that is shown by a laboratory test to be a microsatellite instability-high (MSI-H) or a mismatch repair deficient (dMMR) solid tumor. It may be used in adults and children to treat:
    • cancer that has spread or cannot be removed by surgery (advanced cancer), and
    • has progressed following treatment, and you have no satisfactory treatment options, or
    • you have colon or rectal cancer, and you have received chemotherapy with fluoropyrimidine, oxaliplatin, and irinotecan but it did not work or is no longer working.
  • This use is approved based on how many patients responded to treatment and how long they responded. Studies are ongoing to provide additional information about clinical benefit.
    It is not known if KEYTRUDA is safe and effective in children with MSI-H cancers of the brain or spinal cord (central nervous system cancers).
  • a kind of cancer called colon or rectal cancer. It may be used as your first treatment when your cancer:
    • has spread or cannot be removed by surgery (advanced colon or rectal cancer), and
    • has been shown by a laboratory test to be microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR).
  • a kind of stomach cancer called gastric or gastroesophageal junction (GEJ) adenocarcinoma that tests positive for “PD-L1.” It may be used when your stomach cancer:
    • has returned or spread (advanced gastric cancer), and
    • you have received 2 or more types of chemotherapy including fluoropyrimidine and chemotherapy that contains platinum, and it did not work or is no longer working, and
    • if your tumor has an abnormal “HER2/neu” gene, you also received a HER2/neu‑targeted medicine and it did not work or is no longer working.
  • This use is approved based on how many patients responded to treatment and how long they responded. Studies are ongoing to provide additional information about clinical benefit.
  • a kind of cancer called esophageal or certain gastroesophageal junction (GEJ) carcinomas that cannot be cured by surgery or a combination of chemotherapy and radiation therapy.
    • It may be used with platinum- and fluoropyrimidine-based chemotherapy medicines.
    • It may be used alone when:
      • you have received one or more types of treatment, and it did not work or it is no longer working, and
      • your tumor is a type called “squamous,” and
      • your tumor tests positive for “PD-L1.”
  • a kind of cancer called cervical cancer that tests positive for “PD-L1.” It may be used when your cervical cancer has returned or has spread or cannot be removed by surgery (advanced cervical cancer), and you have received chemotherapy, and it did not work or is no longer working.
  • This use is approved based on how many patients responded to treatment and how long they responded. Studies are ongoing to provide additional information about clinical benefit.
  • a kind of liver cancer called hepatocellular carcinoma. It may be used after you have received the medicine sorafenib.
  • This use is approved based on how many patients responded to treatment and how long they responded. Studies are ongoing to provide additional information about clinical benefit.
  • a kind of skin cancer called Merkel cell carcinoma (MCC) in adults and children. It may be used when your cancer has spread or returned.
  • This use is approved based on how many patients responded to treatment and how long they responded. Studies are ongoing to provide additional information about clinical benefit.
  • a kind of kidney cancer called renal cell carcinoma (RCC). It may be used with the medicine axitinib as your first treatment when your kidney cancer has spread or cannot be removed by surgery (advanced RCC).
  • a kind of skin cancer called cutaneous squamous cell carcinoma (cSCC). It may be used when your skin cancer has returned or spread, and cannot be cured by surgery or radiation.
  • a kind of cancer called triple-negative breast cancer (TNBC). It may be used with chemotherapy medicines when your breast cancer:
    • has returned and cannot be removed by surgery or has spread, and
    • tests positive for “PD-L1.”
  • This use is approved based on the amount of time until patients’ disease got worse. Studies are ongoing to provide additional information about clinical benefit.

PD-L1 = programmed death ligand 1;
EGFR = epidermal growth factor receptor;
ALK = anaplastic lymphoma kinase;
HER2/neu = human epidermal growth factor receptor 2.

Important Safety Information

KEYTRUDA is a medicine that may treat certain cancers by working with your immune system. KEYTRUDA can cause your immune system to attack normal organs and tissues in any area of your body and can affect the way they work. These problems can sometimes become severe or life-threatening and can lead to death. You can have more than one of these problems at the same time. These problems may happen any time during treatment or even after your treatment has ended.

Call or see your health care provider right away if you develop any signs or symptoms of the following problems or if they get worse. These are not all of the signs and symptoms of immune system problems that can happen with KEYTRUDA:

Lung problems: cough, shortness of breath, or chest pain.

Intestinal problems: diarrhea (loose stools) or more frequent bowel movements than usual; stools that are black, tarry, sticky, or have blood or mucus; or severe stomach-area (abdomen) pain or tenderness.

Liver problems: yellowing of your skin or the whites of your eyes; severe nausea or vomiting; pain on the right side of your stomach area (abdomen); dark urine (tea colored); or bleeding or bruising more easily than normal.

Hormone gland problems: headaches that will not go away or unusual headaches; eye sensitivity to light; eye problems; rapid heartbeat; increased sweating; extreme tiredness; weight gain or weight loss; feeling more hungry or thirsty than usual; urinating more often than usual; hair loss; feeling cold; constipation; your voice gets deeper; dizziness or fainting; changes in mood or behavior, such as decreased sex drive, irritability, or forgetfulness.

Kidney problems: decrease in the amount of your urine; blood in your urine; swelling of your ankles; loss of appetite.

Skin problems: rash; itching; skin blistering or peeling; painful sores or ulcers in your mouth or in your nose, throat, or genital area; fever or flu-like symptoms; swollen lymph nodes.

Problems can also happen in other organs and tissues. Signs and symptoms of these problems may include: chest pain; irregular heartbeat; shortness of breath; swelling of ankles; confusion; sleepiness; memory problems; changes in mood or behavior; stiff neck; balance problems; tingling or numbness of the arms or legs; double vision; blurry vision; sensitivity to light; eye pain; changes in eyesight; persistent or severe muscle pain or weakness; muscle cramps; low red blood cells; bruising.

Infusion reactions that can sometimes be severe or life-threatening. Signs and symptoms of infusion reactions may include chills or shaking, itching or rash, flushing, shortness of breath or wheezing, dizziness, feeling like passing out, fever, and back pain.

Rejection of a transplanted organ. Your health care provider should tell you what signs and symptoms you should report and they will monitor you, depending on the type of organ transplant that you have had.

Complications, including graft-versus-host disease (GVHD), in people who have received a bone marrow (stem cell) transplant that uses donor stem cells (allogeneic). These complications can be serious and can lead to death. These complications may happen if you underwent transplantation either before or after being treated with KEYTRUDA. Your health care provider will monitor you for these complications.

Getting medical treatment right away may help keep these problems from becoming more serious. Your health care provider will check you for these problems during treatment with KEYTRUDA. They may treat you with corticosteroid or hormone replacement medicines. They may also need to delay or completely stop treatment with KEYTRUDA if you have severe side effects.

Before you receive KEYTRUDA, tell your health care provider if you have immune system problems such as Crohn’s disease, ulcerative colitis, or lupus; have had an organ transplant or have had or plan to have a bone marrow (stem cell) transplant that uses donor stem cells (allogeneic); have had radiation treatment in your chest area; have a condition that affects your nervous system, such as myasthenia gravis or Guillain-Barré syndrome.

If you are pregnant or plan to become pregnant, tell your health care provider. KEYTRUDA can harm your unborn baby. If you are able to become pregnant, you will be given a pregnancy test before you start treatment. Use effective birth control during treatment and for at least 4 months after your final dose of KEYTRUDA. Tell them right away if you think you may be pregnant or you become pregnant during treatment with KEYTRUDA.

Tell your health care provider if you are breastfeeding or plan to breastfeed. It is not known if KEYTRUDA passes into your breast milk. Do not breastfeed during treatment with KEYTRUDA and for 4 months after your final dose of KEYTRUDA.

Tell your health care provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Common side effects of KEYTRUDA when used alone include feeling tired; pain, including pain in muscles, bones or joints and stomach area (abdominal) pain; decreased appetite; itching; diarrhea; nausea; rash; fever; cough; shortness of breath; and constipation.

In children, when KEYTRUDA is used alone, fever, vomiting, upper respiratory tract infection, headache, and low levels of white blood cells and red blood cells (anemia) are more common than in adults.

Common side effects of KEYTRUDA when given with certain chemotherapy medicines include feeling tired or weak; nausea; constipation; diarrhea; decreased appetite; rash; vomiting; cough; trouble breathing; fever; hair loss; inflammation of the nerves that may cause pain, weakness, and paralysis in the arms and legs; swelling of the lining of the mouth, nose, eyes, throat, intestines, or vagina; mouth sores; headache; and weight loss.

Common side effects of KEYTRUDA when given with axitinib include diarrhea; feeling tired or weak; high blood pressure; liver problems; low levels of thyroid hormone; decreased appetite; blisters or rash on the palms of your hands and soles of your feet; nausea; mouth sores or swelling of the lining of the mouth, nose, eyes, throat, intestines, or vagina; hoarseness; rash; cough; and constipation.

These are not all the possible side effects of KEYTRUDA. Talk to your health care provider for medical advice about side effects.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

Please read the accompanying Medication Guide for KEYTRUDA and discuss it with your doctor. The physician Prescribing Information also is available.