Bone marrow suppression. This is a decrease in the number of white blood cells, red blood cells, and platelets. This may raise your risk of infection, make you tired and weak (fatigue), and raise your risk of bleeding.
Risk of severe and life-threatening infections, including tuberculosis, hepatitis B, and shingles, in patients with risk factors for these infections. A rare virus can cause an infection that affects your central nervous system. The central nervous system is made up of your brain and spinal cord. You could feel extreme tiredness, agitation, confusion, have trouble understanding or speaking, trouble thinking and/or memory loss, difficulty walking, eyesight changes, numbness or lack of strength to your arms, legs, face, or body, or seizures. If you start to have any of these symptoms let your doctor know right away. This medicine may raise your risk of getting a second cancer, such as skin cancer. Increase in your cholesterol and triglyceride levels Typical signs and symptoms of your cancer may return when you stop treatment with ruxolitinib. The use of this type of medicine, a JAK inhibitor, for the treatment of rheumatoid arthritis, has been shown to raise the risk of getting a second cancer such as lymphoma and other cancers. This risk is increased in people who currently smoke or have smoked in the past.