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. These problems may happen anytime during treatment or even after your treatment has ended.
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Taking KEYTRUDA
How does KEYTRUDA work?
Immunotherapy treatment tips
Tips for managing your treatment
Call or see your doctor right away if you develop any symptoms of the following problems or these symptoms get worse:
Lung problems (pneumonitis)
Shortness of breath
Chest pain
New or worse cough
Intestinal problems (colitis) that can lead to tears or holes in your intestine
Diarrhea or more bowel movements than usual
Stools that are black, tarry, sticky, or have blood or mucus
Severe stomach-area (abdomen) pain or tenderness
Liver problems, including hepatitis
Yellowing of your skin or the whites of your eyes
Nausea or vomiting
Pain on the right side of your stomach area (abdomen)
Dark urine
Bleeding or bruising more easily than normal
Kidney problems, including nephritis and kidney failure
Change in the amount or color of your urine
Skin problems
Rash
Itching
Blisters, peeling or skin sores
Painful sores or ulcers in your mouth or in your nose, throat, or genital area
Hormone gland problems (especially the thyroid, pituitary, adrenal glands, and pancreas)
Rapid heart beat
Weight loss or weight gain
Increased sweating
Feeling more hungry or thirsty
Urinating more often than usual
Hair loss
Feeling cold
Constipation
Your voice gets deeper
Muscle aches
Feeling very weak
Dizziness or fainting
Headaches that will not go away or unusual headache
Problems in other organs
Changes in eyesight
Severe or persistent muscle or joint pains
Severe muscle weakness
Low red blood cells (anemia)
Swollen lymph nodes, rash or tender lumps on skin, cough, shortness of breath, vision changes, or eye pain (sarcoidosis)
Confusion, fever, muscle weakness, balance problems, nausea, vomiting, stiff neck, memory problems, or seizures (encephalitis)
Pain, numbness, tingling, or weakness in your arms or legs, or bladder or bowel problems, including the need to urinate more often, leaking of urine, trouble urinating, or constipation (myelitis)
Shortness of breath, irregular heartbeat, feeling tired, or chest pain (myocarditis)
Infusion (IV) reactions that can sometimes be severe and life-threatening
Chills or shaking
Shortness of breath or wheezing
Itching or rash
Flushing
Dizziness
Fever
Feeling like passing out
Rejection of a transplanted organ. People who have had an organ transplant may have an increased risk of organ transplant rejection. Your doctor should tell you what signs and symptoms you should report and 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 severe and can lead to death. These complications may happen if you underwent transplantation either before or after being treated with KEYTRUDA. Your doctor will monitor you for the following signs and symptoms: skin rash, liver inflammation, stomach-area (abdominal) pain, and diarrhea.
Getting medical treatment right away may help keep these problems from becoming more serious. Your doctor will check you for these problems during treatment with KEYTRUDA. Your doctor may treat you with corticosteroid or hormone replacement medicines. Your doctor may also need to delay or completely stop treatment with KEYTRUDA, if you have severe side effects.
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