Get emergency medical help if you have signs of an allergic reaction to Yervoy (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
Some side effects may occur during the injection. Tell your caregiver if you feel dizzy, light-headed, short of breath, itchy, tingly, chilled, or feverish.
Serious and sometimes fatal reactions may occur during treatment with Yervoy or months after stopping. Call your doctor right away if you have symptoms such as:
severe or ongoing diarrhea, severe stomach pain, bloody or tarry stools;
fever, swollen glands, body aches;
new or worsening skin rash, itching, or blistering;
chest pain, irregular heartbeats;
severe muscle weakness, ongoing pain in your muscles or joints;
numbness or tingling in your hands or feet;
vision problems, eye pain or redness;
lung problems - new or worsening cough, chest pain, feeling short of breath;
kidney problems - little or no urination, swelling in your feet or ankles, blood in your urine;
liver problems - right-sided upper stomach pain, tiredness, bruising or bleeding, dark urine, yellowing of your skin or eyes;
signs of a hormonal disorder - frequent or unusual headaches, lack of energy, dizziness, fainting, mood or behavior changes, increased thirst or urination, feeling cold, weight gain, or weight loss; or
symptoms of brain swelling - confusion, headache, memory problems, hallucinations, neck stiffness, drowsiness, seizure (convulsions).
Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.
Common Yervoy side effects may include:
fever, cough, shortness of breath;
nausea, vomiting, stomach pain, loss of appetite;
diarrhea, constipation;
weight loss;
hormonal problems;
rash or itching;
headache, dizziness, tiredness;
sleep problems (insomnia); or
pain in your muscles, joints, or bones.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Yervoy side effects (more detail)
