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URL of this page: https://medlineplus.gov/druginfo/meds/a614048.html

Pembrolizumab Injection

pronounced as (pem'' broe liz' ue mab)

Why is this medication prescribed?

Pembrolizumab injection is used alone or in combination with other chemotherapy medications to treat certain types of melanoma (a type of skin cancer), Merkel cell carcinoma (MCC; a type of skin cancer), and cutaneous squamous cell carcinoma (CSCC; skin cancer). It is also used to prevent the return of melanoma after surgery. Pembrolizumab injection is also used alone and/or in combination with other chemotherapy medications to treat certain types of lung cancer (non-small-cell lung cancer; NSCLC), head and neck cancer, Hodgkin's lymphoma (Hodgkin's disease), primary mediastinal B-cell lymphoma (PMBCL; non-Hodgkin lymphoma), urothelial cancer (cancer of the lining of the bladder and other parts of the urinary tract), bladder cancer, colorectal cancer (cancer that begins in the large intestine), gastric cancer (cancer of the stomach), esophageal cancer (cancer of the tube that connects your throat to your stomach), cervical cancer (cancer that begins in the opening of the uterus [womb]), cancer of the endometrium (lining of the uterus), hepatocellular carcinoma (HCC; a type of liver cancer), biliary tract cancer (BTC; cancer in the organs and ducts that make and store bile, the liquid made by the liver), renal cell carcinoma (RCC, a type of cancer that begins in the kidneys), breast cancer, and certain other solid tumors. Pembrolizumab injection is in a class of medications called monoclonal antibodies. It works by helping your immune system to slow or stop the growth of cancer cells.

Your doctor will review your specific type of cancer and past treatment history and other available treatments to determine if pembrolizumab is right for you.

How should this medicine be used?

Pembrolizumab injection comes as a powder to be mixed with liquid and injected intravenously (into a vein) over 30 minutes by a doctor or nurse in a hospital or medical facility. It is usually injected once every 3 or 6 weeks for as long as your doctor recommends that you receive treatment.

Pembrolizumab injection may cause serious reactions during, or shortly after the infusion of the medication. If you experience any of the following symptoms, tell your doctor immediately: flushing, fever, chills, shaking, dizziness, feeling faint, shortness of breath, difficulty breathing, back pain, itching, rash, or hives.

Your doctor may delay or stop your treatment with pembrolizumab injection, or treat you with additional medications, depending on your response to the medication and any side effects that you experience. Talk to your doctor about how you are feeling during your treatment.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with pembrolizumab injection and each time you receive a dose. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer's website to obtain the Medication Guide.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before receiving pembrolizumab injection,

  • tell your doctor and pharmacist if you are allergic to pembrolizumab, any other medications, or any of the ingredients in pembrolizumab injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while you are receiving pembrolizumab injection. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have ever had an organ or bone marrow transplant and if you have or have ever had radiation therapy to your chest area; an autoimmune disease (condition in which the immune system attacks a healthy part of the body) such as Crohn's disease (condition in which the immune system attacks the lining of the digestive tract causing pain, diarrhea, weight loss, and fever), ulcerative colitis (condition which causes swelling and sores in the lining of the colon [large intestine] and rectum), or lupus (condition in which the immune system attacks many tissues and organs including the skin, joints, blood, and kidneys); diabetes; thyroid problems; any type of lung disease or breathing problems; any condition that affects your nervous system such as myasthenia gravis (a disorder of the nervous system that causes muscle weakness) or Guillain-Barré syndrome (weakness, tingling, and possible paralysis due to sudden nerve damage); or kidney or liver disease.
  • tell your doctor if you are pregnant or plan to become pregnant. You will have to take a pregnancy test before starting treatment. You should not become pregnant while you are receiving pembrolizumab injection and for 4 months after your final dose. Talk to your doctor about birth control methods that will work for you. If you become pregnant while receiving pembrolizumab injection, call your doctor immediately. Pembrolizumab injection may harm the fetus.
  • tell your doctor if you are breastfeeding or plan to breastfeed. Your doctor may tell you not to breastfeed while receiving pembrolizumab injection, and for 4 months after your final dose.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What side effects can this medication cause?

Pembrolizumab injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • muscle, joint, or bone pain
  • changes in skin color
  • dry skin
  • extreme tiredness or lack of energy
  • nausea
  • vomiting
  • constipation
  • difficulty falling asleep or staying asleep
  • hair loss
  • change in sense of taste
  • dry eyes

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • blisters or peeling skin; skin redness; rash; or itching
  • painful sores or ulcers in mouth, nose, throat, or genital area
  • fever or flu-like symptoms
  • shortness of breath
  • swollen glands
  • chest pain
  • new or worsening cough
  • diarrhea
  • stools that are black, tarry, sticky, or contain blood or mucus
  • severe abdominal pain
  • severe nausea and vomiting
  • increased or decreased appetite
  • increased thirst
  • pain in upper right part of the stomach
  • yellowing of the skin or eyes
  • easy bleeding or bruising
  • fast or irregular heartbeat
  • changes in weight (gain or loss)
  • hair loss
  • increased sweating
  • feeling cold
  • deepening of voice or hoarseness
  • changes in mood or behavior
  • decreased sex drive
  • swelling in front of the neck (goiter)
  • tingling and weakness in the feet, legs, hands, and arms
  • stiff neck
  • severe or persistent headache
  • severe or persistent muscle weakness or pain
  • dizziness or lightheadedness
  • fainting
  • change in amount or color of urine
  • pain or a burning sensation while urinating
  • blood in urine
  • swelling of feet, ankles, or lower legs
  • changes in vision, including sensitivity to light, eye pain
  • feeling confused

Pembrolizumab injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to pembrolizumab injection. For some conditions, your doctor will order a lab test before you begin your treatment to see whether your cancer can be treated with pembrolizumab.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Keytruda®
Last Revised - 01/15/2024