Tips for managing & reporting side effects

The tips included within this section come from organizations focused on supporting people with cancer.

This information is not meant to replace your doctor's advice. Be sure to talk to your doctor before you try any of these tips.

You are encouraged to report negative side effects of prescription drugs to the FDA.
Visit or call 1-800-FDA-1088. You can also call 1-800-GILEAD-5 (1-800-445-3235).

One common side effect of ZYDELIG® therapy is diarrhea, or frequent and watery bowel movements. Avoid using ZYDELIG with other drugs that cause diarrhea.

Diarrhea can happen anytime, even several months after you begin treatment. Be sure to tell your doctor or nurse right away if you notice any increase in the number of bowel movements you have in a day. If you have severe diarrhea while taking ZYDELIG, your doctor may completely stop your treatment, stop your treatment for a period of time, or change your dose of ZYDELIG. Reporting diarrhea is especially important because some cases can be managed to allow you to stay on therapy. In a series of clinical trials, some patients stopped therapy. Of the patients who experienced severe diarrhea, 67% were started at a lower dose. Of those patients, 58% who restarted treatment didn’t experience severe diarrhea again.2 Tell your doctor or nurse if you experience any increase in your number of daily bowel movements.

Tips to help manage diarrhea
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Eat smaller meals more often3: Instead of 3 big meals, eat 6 to 8 small meals each day.
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Drink more liquids each day3,4: Drink 8 to 12 cups of liquid per day. Clear broth, gelatin, or an electrolyte drink are good choices for most people. Talk to your doctor to make sure it is safe for you.
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Avoid these foods and drinks3-5:
  • Coffee, tea, alcohol, and sweets
  • High-fiber foods, such as whole-grain breads, granola, and bran cereals
  • Raw vegetables and fruits. Most canned fruits and vegetables are okay
  • Foods that cause gas, like broccoli and cabbage
  • Fried, greasy, or spicy foods
  • Milk, cheese, and other dairy products
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Anti-diarrhea medicine: Severe diarrhea caused by ZYDELIG doesn’t respond well to common anti-diarrhea medicines. Ask your doctor about other treatment options.

Make sure to tell your doctor or nurse if your diarrhea continues.

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One of the most common side effects of ZYDELIG therapy is extreme tiredness, or fatigue. You may be experiencing fatigue if you can't seem to get enough sleep, have trouble focusing, or sometimes get confused.6 Be sure to tell your doctor or nurse as early as possible if you experience fatigue.

Tips to help manage fatigue
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Be active7: Believe it or not, sometimes a little physical activity can go a long way toward relieving fatigue. Your doctor can tell you how to add exercise to your day.
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"De-stress" your life7: If you’re feeling stressed, talk to your doctor, a counselor, family member, friend, or support group about it. Doing some relaxation exercises may also help.
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Get your sleep6,7: Having good sleep habits is another way to manage fatigue. Try to go to bed and wake up at the same time every day. Avoid taking long naps during the day.
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While taking ZYDELIG, you may experience nausea—the feeling of being sick to your stomach. Be sure to tell your doctor or nurse as early as possible if you experience nausea.

Tips to help manage nausea
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Avoid certain foods8: If you’re experiencing nausea, it’s best to avoid greasy, fried, salty, sweet, or spicy foods. "Bland” choices are the best bet. If certain smells bother you, ask others to cook for you, and let your food cool down before eating it.
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Eat and drink enough5,8: If you're having a hard time drinking a full glass of water at a time, try taking small sips throughout the day. Instead of eating 3 big meals per day, try having 5-6 small ones.
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Take anti-nausea medicine8: Your doctor may prescribe you something to relieve your symptoms.
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Tell your doctor or nurse right away if you have a fever while taking ZYDELIG. Fever may be a sign of infection. It is important to report fever or any signs of an infection to a doctor or nurse as early as possible.

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Patient & caregiver resources

Find downloadable resources to help you get and stay informed about your disease and treatment

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Financial information & nurse support

Learn more about the financial information and nurse support offerings that may be available to you while on ZYDELIG treatment

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  1. ZYDELIG® (idelalisib) [Prescribing Information]. Foster City, CA: Gilead Sciences, Inc.; rev October 2020.
  2. Data on file. Gilead Sciences, Inc. 2019.
  3. Diarrhea and cancer treatment. National Cancer Institute website. Revised August 9, 2018. Accessed September 15, 2020.
  4. Diarrhea. American Cancer Society website. Accessed September 15, 2020.
  5. Eating hints: before, during, and after cancer treatment. National Cancer Institute website. Accessed September 15, 2020.
  6. Fatigue (PDQ®)–patient version. National Cancer Institute website. Updated June 30, 2017. Accessed September 15, 2020.
  7. Fatigue and cancer fatigue. Chemocare website. Accessed September 15, 2020.
  8. Nausea and vomiting in people with cancer. National Cancer Institute website. Accessed September 15, 2020.