Idelalisib (Zydelig®)

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About This Drug

Idelalisib is used to treat cancer. It is given orally (by mouth).

Possible Side Effects

  • Decrease in the number of white blood cells. This may raise your risk of infection.
  • Nausea
  • Diarrhea (loose bowel movements)
  • Pain in your abdomen
  • Tiredness
  • Fever
  • Changes in your liver function
  • Cough
  • Pneumonia
  • Rash

Note: Each of the side effects above was reported in 20% or greater of patients treated with idelalisib. Not all possible side effects are included above.

Warnings and Precautions

  • Severe allergic skin reaction which can very rarely be life-threatening. You may develop blisters on your skin that are filled with fluid or a severe red rash all over your body that may be painful.
  • Allergic reactions, including anaphylaxis are rare but may happen in some patients. Signs of allergic reaction to this drug may be swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way. If this happens, do not take another dose of this drug. You should get urgent medical treatment.
  • Severe infections, including viral, bacterial and fungal, which can be life-threatening.
  • Severe decrease in the number of white blood cells. This may increase your risk of severe infections, including viral, bacterial and fungal, which can be life-threatening.
  • Severe changes in your liver function, which can cause liver failure and be life-threatening.
  • Severe diarrhea, and/or colitis, which is swelling (inflammation) in the colon - symptoms are diarrhea, stomach cramping, and sometimes blood in the bowel movements. Very rarely, you may get a hole in your stomach, small and/or large intestine which may be life-threatening.
  • Inflammation (swelling) of the lungs which can be life-threatening. You may have a dry cough or trouble breathing.

Note: Some of the side effects above are very rare. If you have concerns and/or questions, please discuss them with your medical team.

How to Take Your Medication

  • Swallow the medicine whole with or without food.
  • Missed dose: If you miss a dose by less than 6 hours, take the missed dose and go back to your normal schedule. If you miss a dose by more than 6 hours, then skip the missed dose and go back to your normal schedule. Do not take 2 doses at the same time or extra doses.
  • If you vomit a dose or miss a dose, contact your doctor.
  • Handling: Wash your hands after handling your medicine, your caretakers should not handle your medicine with bare hands and should wear latex gloves.
  • This drug may be present in the saliva, tears, sweat, urine, stool, vomit, semen, and vaginal secretions. Talk to your doctor and/or your nurse about the necessary precautions to take during this time.
  • Storage: Store this medicine in the original container at room temperature. Do not use of the seal over the bottle opening is missing or broken.
  • Disposal of unused medicine: Do not flush any expired and/or unused medicine down the toilet or drain unless you are specifically instructed to do so on the medication label. Some facilities have take-back programs and/or other options. If you do not have a take-back program in your area, then please discuss with your nurse or your doctor how to dispose of unused medicine.

Treating Side Effects

  • Manage tiredness by pacing your activities for the day.
  • Be sure to include periods of rest between energy-draining activities.
  • To decrease the risk of infection, wash your hands regularly.
  • Avoid close contact with people who have a cold, the flu, or other infections.
  • Take your temperature as your doctor or nurse tells you, and whenever you feel like you may have a fever.
  • Drink plenty of fluids (a minimum of eight glasses per day is recommended).
  • If you throw up or have loose bowel movements, you should drink more fluids so that you do not become dehydrated (lack of water in the body from losing too much fluid).
  • If you have diarrhea, eat low-fiber foods that are high in protein and calories and avoid foods that can irritate your digestive tracts or lead to cramping.
  • Ask your nurse or doctor about medicine that can lessen or stop your diarrhea.
  • To help with nausea and vomiting, eat small, frequent meals instead of three large meals a day. Choose foods and drinks that are at room temperature. Ask your nurse or doctor about other  helpful tips and medicine that is available to help stop or lessen these symptoms.
  • If you get a rash, do not put anything on it unless your doctor or nurse says you may. Keep the area around the rash clean and dry. Ask your doctor for medicine if your rash bothers you.
  • Keeping your pain under control is important to your well-being. Please tell your doctor or nurse if you are experiencing pain.

Food and Drug Interactions

  • This drug may interact with grapefruit and grapefruit juice. Talk to your doctor as this could make side effects worse.
  • Check with your doctor or pharmacist about all other prescription medicines and over-the-counter medicines and dietary supplements (vitamins, minerals, herbs and others) you are taking before starting this medicine as there are known drug interactions with idelalisib. Also, check with your doctor or pharmacist before starting any new prescription or over-the-counter medicines, or dietary supplements to make sure that there are no interactions.
  • Avoid the use of St. John’s Wort while taking idelalisib as this may lower the levels of the drug in your body, which can make it less effective.

When to Call the Doctor

Call your doctor or nurse if you have any of these symptoms and/or any new or unusual symptoms:

  • Fever of 100.4 F (38 C) or higher
  • Chills
  • Pain in your chest
  • Dry cough
  • Coughing yellow, green, or bloody mucus
  • Wheezing or trouble breathing
  • Tiredness that interferes with your daily activities
  • Nausea that stops you from eating or drinking and/or is not relieved by prescribed medicines
  • Throwing up more than 3 times a day
  • Diarrhea, 4 times in one day or diarrhea with lack of strength or a feeling of being dizzy
  • Severe pain in your abdomen that does not go away
  • Difficulty swallowing
  • Blood in your stool
  • Signs of allergic reaction: swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way. If this happens, call 911 for emergency care.
  • Signs of possible liver problems: dark urine, pale bowel movements, bad stomach pain, feeling very tired and weak, unusual itching, or yellowing of the eyes or skin
  • Flu-like symptoms: fever, headache, muscle and joint aches, and fatigue (low energy, feeling weak)
  • A new rash and/or itching that is not relieved by prescribed medicines
  • If you think you may be pregnant or may have impregnated your partner

Reproduction Warnings

  • Pregnancy warning: This drug may have harmful effects on the unborn baby. Women of childbearing potential should use effective methods of birth control during your cancer treatment and for at least 1 month after treatment. Men with female partners of childbearing potential should use effective methods of birth control during your cancer treatment and for 3 months after your cancer treatment. Let your doctor know right away if you think you may be pregnant or may have impregnated your partner.
  • Breastfeeding warning: It is not known if this drug passes into breast milk. For this reason, women should not breastfeed during treatment and for at least 1 month after treatment because this drug could enter the breast milk and cause harm to a breastfeeding baby.
  • Fertility warning: In men and women both, this drug may affect your ability to have children in the future. Talk with your doctor or nurse if you plan to have children. Ask for information on sperm or egg banking.

Revised June 2019

This patient information was developed by Via Oncology, LLC © 2019. This information is not intended to be used as a substitute for professional medical advice, diagnosis, or treatment. You should not rely entirely on this information for your health care needs. Ask your own doctor or health care provider any specific medical questions that you have.

CLIENT acknowledges that the Via Pathways and Via Portal are information management tools only, and that Via Oncology, LLC has not represented the Via Pathways or Via Portal as having the ability to diagnose disease, prescribe treatment, or perform any other tasks that constitute the practice of medicine. The clinical information contained in the Via Pathways and Via Portal are intended  as a supplement to, and not a substitute for, theknowledge, expertise, skill, and judgment of physicians, pharmacists and other healthcare professionals involved with patient care at CLIENT facilities.