When This Medicine Should Not Be Used:
This medicine is not right for everyone. Do not use it if you had an allergic reaction to idelalisib, or if you are pregnant.

How to Use This Medicine:
Tablet

• Medicines used to treat cancer are very strong and can have many side effects. Before receiving this medicine, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.
• Your doctor will tell you how much medicine to use. Do not use more than directed.
• Swallow the tablet whole. Do not crush, break, or chew it.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Missed dose: If you miss a dose, you may still take it up to 6 hours after the time you normally take it. However, if it is more than 6 hours, skip the missed dose and go back to your regular dosing schedule. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Some medicines can affect how idelalisib works. Tell your doctor if you are using carbamazepine, ketoconazole, phenytoin, rifampin, or St John's wort.

Warnings While Using This Medicine:

• It is not safe to take this medicine during pregnancy. It could harm an unborn baby. Tell your doctor right away if you become pregnant. You should not become pregnant while you are using this medicine and for at least 1 month after stopping it.
• Tell your doctor if you are breastfeeding, or if you have liver disease or lung problems.
• This medicine may cause the following problems:
  
  • Liver or lung problems
  • Bowel perforation
  • Serious skin reactions
  • An increased risk of infection
• This medicine can cause diarrhea. Call your doctor if the diarrhea becomes severe, does not stop, or is bloody. Do not take any medicine to stop diarrhea until you have talked to your doctor. Diarrhea can occur 2 months or more after you stop taking this medicine.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:
Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Abdominal pain with nausea, vomiting, fever, chills
• Blistering, peeling, or red skin rash
• Chest pain, trouble breathing
• Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
• Fever, chills, cough, sore throat, and body aches
• Severe diarrhea that may contain blood

If you notice these less serious side effects, talk with your doctor:

• Fever
• Mild diarrhea, nausea, vomiting, loss of appetite
• Mild skin rash
• Tiredness or weakness

If you notice other side effects that you think are caused by this medicine, tell your doctor.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088