Classification: Kinase Inhibitor
Ibrutinib is a type of targeted therapy called a kinase inhibitor. This means it works by targeting receptors present on the cancer cells. This medication specifically interferes with the function of Bruton's tyrosine kinase (BTK), which is found in excess on cancerous B cells. By interfering with BTK, ibrutinib interferes with the cancerous B cell's growth.
Ibrutinib comes in a capsule form that is typically taken once a day, at approximately the same time, with or without food. Swallow the capsule whole with water; do not open, crush or chew them. If you miss a dose, take it as soon as you remember that day. However, if it is the next day, just take that day's dose at the scheduled time, do not take more than one dose to make up for a missed dose.
The blood levels of this medication can be affected by certain foods and medications, so they should be avoided. These include: grapefruit, grapefruit juice, and Seville oranges (often used in marmalade), St. John's Wort, several cardiac medications and many anti-fungal and antibiotic medications. Be sure to tell your healthcare provider about all medications and supplements you take.
Below are some of the possible side effects and suggestions for dealing with them. Be sure to tell your oncology team if you are experiencing any of these problems.
White blood cells (WBC) are important for fighting infection. While receiving treatment, your WBC count can drop, putting you at a higher risk of getting an infection. You should let your doctor or nurse know right away if you have a fever (temperature greater than 100.4° F), sore throat or cold, shortness of breath, cough, burning with urination, or a sore that doesn't heal.
Tips to preventing infection:
For more suggestions, read the Neutropenia Tip Sheet.
Your red blood cells are responsible for carrying oxygen to the tissues in your body. When the red cell count is low, you may feel tired or weak. You should let your doctor or nurse know if you experience any shortness of breath, difficulty breathing or pain in your chest. If the count gets too low, you may receive a blood transfusion. Read the anemia tip sheet for more information.
Platelets help your blood clot, so when the count is low you are at a higher risk of bleeding. Let your doctor or nurse know if you have any bleeding or excess bruising, including nose bleeds, bleeding gums or blood in your urine or stool. If the platelet count becomes too low, you may receive a transfusion of platelets.
Read the thrombocytopenia tip sheet for more information.
Diarrhea can be severe and can cause dangerous dehydration. Be sure to report diarrhea to your healthcare team.
Your oncology team can recommend medications to relieve diarrhea. Also, try eating low-fiber, bland foods, such as white rice and boiled or baked chicken. Avoid raw fruits, vegetables, whole grain breads, cereals and seeds. Soluble fiber is found in some foods and absorbs fluid, which can help relieve diarrhea. Foods high in soluble fiber include: applesauce, bananas (ripe), canned fruit, boiled potatoes, white rice and products made with white flour, oatmeal, cream of rice, cream of wheat, and farina. Drink 8-10 glasses on non-alcoholic, un-caffeinated fluid a day to prevent dehydration. Read Low Fiber Diet for Diarrhea for more tips.
Take anti-nausea medications as prescribed. If you continue to have nausea or vomiting, notify your doctor or nurse so they can help you manage this side effect. In addition, dietary changes may help. Avoid things that may worsen the symptoms, such as heavy or greasy/fatty, spicy or acidic foods (lemons, tomatoes, oranges). Try antacids, (e.g. milk of magnesia, calcium tablets such as Tums), saltines, or ginger ale to lessen symptoms. Read the Nausea & Vomiting Tip Sheet for more suggestions.
Call your doctor or nurse if you are unable to keep fluids down for more than 12 hours or if you feel lightheaded or dizzy at any time.
While on cancer treatment you may need to adjust your schedule to manage fatigue. Plan times to rest during the day and conserve energy for more important activities. Exercise can help combat fatigue; a simple daily walk with a friend can help. Talk to your healthcare team and see OncoLink's section on fatigue for helpful tips on dealing with this side effect.
Exposure of an unborn child to this medication could cause birth defects, so you should not become pregnant or father a child while on this medication. Even if your menstrual cycle stops or you believe your sperm is affected, effective birth control is necessary during treatment and up to 2 weeks after stopping treatment.
Ibrutinib can affect the function of your kidneys. Your healthcare provider will monitor your kidney function with blood tests, but it is important for you to remain well-hydrated. Drink at least 8-10 glasses of non-alcoholic, uncaffeinated beverages a day.
In studies, some patients developed a second cancer, including skin cancers. Report any abnormalities to your healthcare provider. Patients also experienced muscle and bone pain and swelling of the legs and feet. If these occur, report this to your healthcare team.