Severe side effects can be life threatening. They may occur right away or up to 2 years after treatment ends.
If you are treated with an immune checkpoint inhibitor, it is important that you are aware of these side effects and that you call your doctor right away if they occur. If caught early, they can be treated. The list below describes dangerous side effects and their symptoms.
Side effect: Inflammation of the lung (pneumonitis)
New or worsening cough
Shortness of breath
Chest pain
Side effect: Inflammation of the liver (hepatitis)
Yellowing of skin (jaundice)
Severe nausea or vomiting
Pain on the right side of your stomach area
Drowsiness
Tea-colored urine
Bleeding or bruising
Feeling less hungry than usual
Side effect: Inflammation of the colon (colitis)
Diarrhea (loose stools) or more bowel movements than normal
Blood in stools or black, tarry, or sticky stools
Severe abdominal pain or tenderness
Hormone or gland problems, especially the thyroid, pituitary, and adrenal glands and the pancreas
Headaches that will not go away
Extreme tiredness
Weight gain or weight loss
Dizziness or fainting
Changes in mood or behavior, such as decreased sex drive, irritability, or forgetfulness
Hair loss
Feeling cold
Constipation
Voice getting deeper
Excessive thirst or increased urination
Side effect: Inflammation of the brain (neuropathy, meningitis, or encephalitis)
Headache
Fever
Tiredness or weakness
Confusion
Memory problems
Sleepiness
Hallucinations (seeing or hearing things that are not there)
Severe muscle weakness
Numbness or tingling in your hands or feet
Extreme sensitivity to light
Neck stiffness
Side effect: Kidney problems, including kidney failure
Change in the color or amount of urine
Blood in the urine
Swelling in the ankles
Loss of appetite
Complicated skin reactions
Rash that affects your quality of life
Blisters covering over 30% of the body
Itching
Ulcers in the mouth, nose, ears, or other mucous membranes, making it difficult to eat or drink
Side effect: Severe infections
Fever
Cough
Flu-like symptoms
Pain when urinating
Side effect: Eye problems (may indicate a more widespread problem)
Blurry vision, double vision, or other vision problems
Eye pain or redness
Side effect: Severe infusion reactions
Chills or shaking
Itching or rash
Flushing
Shortness of breath or wheezing
Swelling of face or lips
Dizziness
Feeling like passing out
Back or neck pain