85-KEYTRUDA

(855-398-7832)
Treatment Overview
Results for KEYTRUDA
Side Effects
Cost, Insurance & Financial Help
Resources & Support

FREQUENTLY ASKED QUESTIONS ABOUT KEYTRUDA and KEYTRUDA QLEX

On this page:

About KEYTRUDA

KEYTRUDA is not chemotherapy or radiation therapy—it is an immunotherapy and it works with your immune system to help fight cancer. Immunotherapies such as KEYTRUDA may stop cancer cells from hiding. KEYTRUDA may enable T cells to find and attack cancer cells. This helps your immune system do what it’s designed to do: detect and fight cancer.

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.

KEYTRUDA is an immunotherapy medicine that may treat certain cancers by working with your immune system. Immunotherapy is a type of cancer treatment that uses your own immune system to help detect and fight cancer. Instead of attacking cancer cells directly, immunotherapy treatments help your body fight cancer.

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.

Your doctor will give you KEYTRUDA into your vein through an intravenous (IV) line. Treatments are given over 30 minutes. Treatments usually take place at your doctor’s office or an infusion clinic.

In adults with certain cancers, KEYTRUDA is usually given every 3 weeks or every 6 weeks depending on the dose that you are receiving. In children, KEYTRUDA is usually given every 3 weeks.

Talk to your doctor about the treatment schedule that is right for you. Your doctor can help answer questions.

Understanding side effects with KEYTRUDA

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

Side effects can happen at any time during your treatment.

Knowing what the side effects are can help you or your care partner more easily recognize them if you start to feel any of the symptoms.

When should I speak up about side effects?

If you have any changes in the way you feel, it’s important to discuss those changes with your health care team.

  • Tell your doctor if you have any side effect that bothers you or that does not go away.
  • Make sure to upload your symptom tracker to your doctor’s patient portal, so you and your doctor can keep an eye on any side effects you may experience and how often they occur.
  • Getting medical treatment right away may help keep these problems from becoming more serious.

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 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)

About KEYTRUDA QLEX

KEYTRUDA QLEX is an FDA-approved immunotherapy. KEYTRUDA QLEX contains KEYTRUDA and berahyaluronidase alfa. Berahyaluronidase alfa allows pembrolizumab to be absorbed into your body more easily when given as a subcutaneous injection.

KEYTRUDA QLEX is a subcutaneous injection given just under the skin by your healthcare provider in 1 minute* every 3 weeks or 2 minutes* every 6 weeks in the stomach area or thigh. Your dosing schedule depends on the treatment plan your doctor prescribes.

*Injection time only. Not total appointment time.

Learn more about KEYTRUDA QLEX:

Yes, KEYTRUDA QLEX is a subcutaneous injection given just under the skin by your healthcare provider in 1 minute* every 3 weeks or 2 minutes* every 6 weeks in the stomach area or thigh. Your dosing schedule depends on the treatment plan your doctor prescribes.

*Injection time only. Not total appointment time.

In this type of injection, a short needle is used to inject the medication just under the skin, into the fatty tissue layer between the skin and the muscle in the stomach area or thigh.

KEYTRUDA QLEX is a subcutaneous injection given just under the skin by your healthcare provider in 1 minute* every 3 weeks or 2 minutes* every 6 weeks in the stomach area or thigh. Your dosing schedule depends on the treatment plan your doctor prescribes.

*Injection time only. Not total appointment time.

KEYTRUDA QLEX is given as an injection under the skin, not into a vein. That is why port surgery is not required. It’s important to note that you may still need a port if your treatment plan involves another treatment, such as chemotherapy.

You and your healthcare provider can choose either your stomach area or thigh for the injection.

Your doctor can help you decide if switching from KEYTRUDA to KEYTRUDA QLEX is right for you at any time during your treatment.

You may need to contact your insurance company for information about your coverage.

Understanding side effects with KEYTRUDA QLEX

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

Side effects can happen at any time during your treatment.

Knowing what the side effects are can help you or your care partner more easily recognize them if you start to feel any of the symptoms.

When should I speak up about side effects?

If you have any changes in the way you feel, it’s important to discuss those changes with your health care team.

  • Tell your doctor if you have any side effect that bothers you or that does not go away.
  • Make sure to upload your symptom tracker to your doctor’s patient portal, so you and your doctor can keep an eye on any side effects you may experience and how often they occur.
  • Getting medical treatment right away may help keep these problems from becoming more serious.

Write down all physical and emotional changes

Even before you get your first injection, 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 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 injections)

Support for KEYTRUDA and KEYTRUDA QLEX

Whether you’ve just been diagnosed or are beginning treatment with KEYTRUDA or KEYTRUDA QLEX, it can be reassuring to know what to expect. Find the support you and your care partner may need:

Questions or concerns about KEYTRUDA and KEYTRUDA QLEX, your cancer, or any cancer treatments you are taking should be directed to your healthcare team.

If you have questions about KEYTRUDA or KEYTRUDA QLEX, please call 85-KEYTRUDA (855-398-7832).

You can learn more about out-of-pocket costs and potential financial assistance options here:

Cost, insurance & financial help for KEYTRUDA
Cost, insurance & financial help for KEYTRUDA QLEX

Need more information about whether your insurance provider covers KEYTRUDA or KEYTRUDA QLEX or about potential financial assistance options?

If you need further information or help paying for KEYTRUDA or KEYTRUDA QLEX (with or without insurance coverage), Merck may be able to help. Contact The Merck Access Program at 855-257-3932. The Merck Access Program can help answer questions like:

  • Does my insurance cover KEYTRUDA or KEYTRUDA QLEX?
  • What are the co-pay assistance options for eligible patients?
  • How can I find out if I’m eligible for the Merck Patient Assistance Program?

Visit The Merck Access Program website for more information and to enroll.

The Merck Access Program

To speak to a Merck Access Program representative:

Please visit Support Near Me, a third-party website where people living with cancer can find local resources. These resources may help with the daily challenges of living with cancer, such as housing, food, transportation, and more.

Continue to SupportNearMe.com

Access to Support Near Me is licensed by Merck solely as a convenience for patients and caregivers. Merck does not control the content of this site and has not taken steps to verify the accuracy of the listing provided. The organizations listed on the site do not imply an endorsement or referral by Merck, nor do they signify the organizations' endorsement of Merck or its products.

About biomarkers

Everyone’s cancer is different. To help develop a treatment plan that’s right for you, your doctor may order biomarker tests. These tests can measure your tumor for different biomarkers, including biomarkers known as MSI or MMR and another biomarker called PD-L1. Biomarker tests may be used to help predict your response to certain treatments, such as KEYTRUDA or KEYTRUDA QLEX.

PD-L1:

Talk to your doctor to see if a PD-L1 biomarker test is right for you.

Non–small cell lung cancer (NSCLC)
Head and neck squamous cell cancer add (HNSCC)
Advanced esophageal cancer
Advanced cervical cancer
Advanced triple-negative breast cancer (TNBC)
Advanced stomach cancer (HER2-negative gastric or GEJ)

MSI/MMR:

Talk to your doctor to see if a laboratory test for the MSI or MMR biomarker is right for you.

Advanced MSI-H/dMMR colorectal cancer (CRC)

PD-1 and PD-L1 are types of proteins found on cells in your body. PD-1 protein is found on immune cells called T cells. It normally acts as a type of “off switch” that helps keep the T cells from attacking other cells in the body. PD-1 attaches to PD-L1, a protein found on some normal (and cancer) cells. This interaction basically tells the T cell to leave the other cell alone and not attack it. Some cancer cells have large amounts of PD-L1, which helps them hide from immune attack.

Therapies that target either PD-1 or PD-L1 can stop them from attaching and help keep cancer cells from hiding.

Learn more about KEYTRUDA and KEYTRUDA QLEX, two immunotherapies that work by blocking the PD-1 pathway.

KEYTRUDA and KEYTRUDA QLEX 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.

Patient and caregiver resource library

Explore our library of downloadable resources, which includes some resources in Spanish, that are designed to help you and your loved ones throughout your treatment with KEYTRUDA or KEYTRUDA QLEX.

You also might be interested in:

FDA-Approved Indications for KEYTRUDA® (pembrolizumab) and KEYTRUDA QLEX™ (pembrolizumab and berahyaluronidase alfa-pmph)

KEYTRUDA and KEYTRUDA QLEX are prescription medicines used to treat:

  • a kind of lung cancer called non–small cell lung cancer (NSCLC).
    • Each may be used in combination with chemotherapy that contains platinum and another chemotherapy medicine before surgery when you have early-stage NSCLC, which can be removed by surgery, and then continued alone after surgery to help prevent your lung cancer from coming back.
    • Each 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 “nonsquamous” and your tumor does not have an abnormal “EGFR” or “ALK” gene.
    • Each 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.”
    • Each 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‑L1” and does not have an abnormal “EGFR” or “ALK” gene.
    • Each 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-L1” and 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.
    • Each may be used as a treatment in adults for your lung cancer to help prevent your lung cancer from coming back after your tumor(s) has been removed by surgery and you have received platinum-based chemotherapy, and you have stage IB and your tumor(s) is 4 cm or greater in size, stage II, or stage IIIA NSCLC.

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of skin cancer called melanoma.
    • Each may be used when your melanoma has spread or cannot be removed by surgery (advanced melanoma).

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective in children with advanced melanoma.

    • Each may be used in adults and children 12 years of age and older with stage IIB, stage IIC, or stage III melanoma, to help prevent melanoma from coming back after it and lymph nodes that contain cancer have been removed by surgery.

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective in children younger than 12 years of age with melanoma.

  • a kind of cancer called head and neck squamous cell cancer (HNSCC).
    • Each may be used alone in adults with HNSCC before surgery when your cancer can be removed by surgery, has spread to nearby tissues, and your tumor tests positive for “PD-L1,” and then continued in combination with radiation with or without cisplatin after surgery, and then continued alone to help prevent your head and neck cancer from coming back.
    • Each 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.
    • Each 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.”
    • Each 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.

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of bladder and urinary tract cancer called urothelial cancer.
    • Each may be used with the medicine enfortumab vedotin in adults when your bladder or urinary tract cancer has spread or cannot be removed by surgery (locally advanced or metastatic urothelial cancer).
    • Each may be used alone when your bladder or urinary tract cancer has spread or cannot be removed by surgery (locally advanced or metastatic urothelial cancer), and you are not able to receive chemotherapy that contains platinum (medicines called either cisplatin or carboplatin).
    • Each may be used alone when your bladder or urinary tract cancer has spread or cannot be removed by surgery (locally advanced or metastatic urothelial cancer), and you have received chemotherapy that contains platinum, and it did not work or is no longer working.
    • Each may be used with the medicine enfortumab vedotin in adults before and after the surgical removal of your bladder when your bladder cancer has spread into the muscle layer of the bladder (muscle invasive bladder cancer [MIBC]) but not to other parts of the body, and you are not able to receive chemotherapy that contains cisplatin.
    • Each may be used alone 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 is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • 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. Each may be used in adults 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.

      • KEYTRUDA also may be used to treat children with this kind of cancer, and KEYTRUDA QLEX also may be used to treat children 12 years and older.

      It is not known if KEYTRUDA QLEX is safe and effective for this use in children younger than 12 years of age.

  • a kind of cancer called colon or rectal cancer. Each may be used 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).

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of stomach cancer called gastric or gastroesophageal junction (GEJ) adenocarcinoma.
    • Each may be used in adults in combination with fluoropyrimidine and platinum chemotherapy as your first treatment when your stomach cancer:
      • is HER2-negative, and your tumor tests positive for “PD-L1,” and
      • has spread or cannot be removed by surgery (advanced gastric cancer).

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for this use in children.

  • 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.
    • Each may be used in combination with platinum- and fluoropyrimidine-based chemotherapy medicines when your tumor tests positive for “PD-L1.”
    • Each 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.”

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of cancer called cervical cancer.
    • Each may be used with chemotherapy and radiation therapy when your cervical cancer has spread nearby to the lower part of your vagina or to pelvic organs or has affected your kidneys (Stage III to IVA FIGO 2014 classification).
    • Each may be used with chemotherapy medicines, with or without the medicine bevacizumab, when:
      • your cervical cancer does not go away (persistent), has returned, or has spread (advanced cervical cancer), and
      • your tumor tests positive for “PD-L1.”
    • Each may be used alone when your cervical cancer:
      • has returned, or has spread (advanced cervical cancer), and
      • you have received chemotherapy, and it did not work or is no longer working, and
      • your tumor tests positive for “PD‑L1.”

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of kidney cancer called renal cell carcinoma (RCC).
    • Each may be used alone if you are at intermediate-high or high risk of your kidney cancer (RCC) coming back after surgery to:
      • remove all or part of your kidney, or
      • remove all or part of your kidney and also surgery to remove cancer that has spread to other parts of the body (metastatic lesions).

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of uterine cancer called advanced endometrial carcinoma.
    • Each may be used with the chemotherapy medicines carboplatin and paclitaxel, and then may be used alone, in adults:
      • when your cancer has spread (advanced), or
      • if your cancer has returned.

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

  • a kind of skin cancer called cutaneous squamous cell carcinoma (cSCC). Each may be used when your skin cancer has returned or spread, and cannot be cured by surgery or radiation.

      It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for this use in children.

  • a kind of cancer called triple-negative breast cancer (TNBC).
    • Each may be used with chemotherapy medicines as treatment before surgery and then continued alone after surgery when you have early-stage breast cancer, and are at high risk of your breast cancer coming back (high-risk early-stage triple-negative breast cancer [TNBC]).
    • Each may be used with chemotherapy medicines when your breast cancer has returned and cannot be removed by surgery or has spread (advanced TNBC), and tests positive for “PD-L1.”

      • It is not known if KEYTRUDA and KEYTRUDA QLEX are safe and effective for these uses in children.

PD-L1 = programmed death ligand 1;

EGFR = epidermal growth factor receptor;

ALK = anaplastic lymphoma kinase;

FIGO = International Federation of Gynecology and Obstetrics;

HER2 = human epidermal growth factor receptor 2.

Important Safety Information

Do not receive KEYTRUDA QLEX if you are allergic to berahyaluronidase, hyaluronidase or any of the inactive ingredients in KEYTRUDA QLEX.

KEYTRUDA and KEYTRUDA QLEX are medicines that may treat certain cancers by working with your immune system. KEYTRUDA and KEYTRUDA QLEX 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 or KEYTRUDA QLEX:

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, injection-related, and allergic reactions that can sometimes be severe or life-threatening. Signs and symptoms of infusion, injection-related, and allergic 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 or tissue. 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 or tissue 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 or KEYTRUDA QLEX. 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 or KEYTRUDA QLEX. They may treat you with corticosteroid or hormone replacement medicines. They may also need to delay or completely stop treatment with KEYTRUDA and KEYTRUDA QLEX if you have severe side effects.

Before you receive KEYTRUDA or KEYTRUDA QLEX, tell your health care provider if you have immune system problems such as Crohn’s disease, ulcerative colitis, or lupus; have had an organ or tissue transplant, including corneal 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 and KEYTRUDA QLEX 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 with KEYTRUDA or KEYTRUDA QLEX and for 4 months after your last dose of KEYTRUDA or KEYTRUDA QLEX. Tell them right away if you think you may be pregnant or you become pregnant during treatment with KEYTRUDA or KEYTRUDA QLEX.

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

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

The most common side effects of KEYTRUDA QLEX when given with certain chemotherapy medicines include nausea; tiredness; and muscle, bone, and joint pain.

The most common side effects observed with KEYTRUDA when used alone, which may be experienced with KEYTRUDA QLEX, include feeling tired; pain, including pain in muscles; rash; diarrhea; fever; cough; decreased appetite; itching; shortness of breath; constipation; bones or joints and stomach-area (abdominal) pain; nausea; and low levels of thyroid hormone.

The most common side effects observed with KEYTRUDA when used alone that are more common in children than adults, which may be experienced with KEYTRUDA QLEX, include fever, vomiting, headache, stomach area (abdominal) pain, and low levels of white blood cells.

The most common side effects observed with KEYTRUDA when given with certain chemotherapy or chemotherapy with radiation therapy medicines, which may be experienced with KEYTRUDA QLEX, 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; weight loss; stomach-area (abdominal) pain; joint and muscle pain; trouble sleeping; blisters or rash on the palms of your hands and soles of your feet; urinary tract infection; low levels of thyroid hormone; skin irritation in the radiation area; trouble swallowing; and dry mouth.

The most common side effects observed with KEYTRUDA when given with enfortumab vedotin, which may be experienced with KEYTRUDA QLEX, include rash; tingling or numbness of the arms or legs; feeling tired; itching; diarrhea; hair loss; weight loss; decreased appetite; dry eye; nausea; constipation; changes in sense of taste; and urinary tract infection.

The most common side effects observed with KEYTRUDA when given with chemotherapy and bevacizumab, which may be experienced with KEYTRUDA QLEX, include tingling or numbness of the arms or legs; hair loss; low red blood cell count; feeling tired or weak; nausea; low white blood cell count; diarrhea; high blood pressure; decreased platelet count; constipation; joint aches; vomiting; urinary tract infection; rash; low levels of thyroid hormone; decreased appetite; fever; mouth sores; and nosebleed.

These are not all the possible side effects of KEYTRUDA or KEYTRUDA QLEX. 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.

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