Idelalisib may cause serious or life threatening liver damage. Tell your doctor if you have or ever have had liver disease. The risk of liver damage may be increased in people taking other medications known to cause liver damage, and in people who already have liver disease. Tell your doctor and pharmacist about the medications you are taking so they can check whether any of your medications may increase the risk that you will develop liver damage during your treatment with idelalisib. If you experience any of the following symptoms, call your doctor immediately: extreme tiredness, loss of appetite, weight loss, nausea, vomiting, unusual bleeding or bruising, yellowing of the skin or eyes, dark yellow or brown-colored urine, pale stools, or pain in the upper right part of the stomach.

Idelalisib may cause diarrhea, colitis (swelling of the large intestine), or holes in the stomach or intestine. Tell your doctor if you have diarrhea or if you have ever had colitis or other conditions that affect your stomach or intestine. The risk of diarrhea may be increased in people taking other medications known to cause diarrhea. Tell your doctor and pharmacist about the medications you are taking so they can check whether any of your medications may increase the risk that you will develop diarrhea during your treatment with idelalisib.If you experience any of the following symptoms, call your doctor immediately: if your number of bowel movements in a day increases by 6 or more , stomach cramps or pain, chills, fever, nausea, or vomiting.

Idelalisib may cause serious or life threatening pneumonitis (swelling of the lungs). Tell your doctor if you have lung disease or breathing problems. If you experience any of the following symptoms, call your doctor immediately: new or worsening cough, difficulty breathing, wheezing, or shortness of breath.

Idelalisib may cause serious or life threatening infections. Tell your doctor if you have an infection, or if you have or have ever had cytomegalovirus (CMV; a viral infection that may cause symptoms in patients with weak immune systems). If you experience any of the following symptoms, call your doctor immediately: fever, sore throat, chills, painful, frequent, or difficult urination, or other signs of infection.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests to check your body’s response to idelalisib.

Talk to your doctor about the risks of taking idelalisib.

Idelalisib is used along with another medication rituximab (Rituxan) to treat chronic lymphocytic leukemia (CLL; a type of cancer that begins in the white blood cells) in people whose cancer came back after receiving other cancer treatments. It is also used to treat certain types of follicular lymphoma (FL; a type of cancer that begins in the white blood cells) and small lymphocytic lymphoma (SLL:a type of cancer that begins in the white blood cells) in people whose cancer came back after being treated with at least 2 other cancer treatments. Idelalisib is in a class of medications called kinase inhibitors. It works by blocking the action of the abnormal protein that signals cancer cells to multiply. This helps stop the spread of cancer cells.

Idelalisib comes as a tablet to take by mouth. It is usually taken with or without food twice a day. Take idelalisib at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take idelalisib exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them.

Your doctor may decrease your dose of idelalisib or tell you to stop taking the medication for a time or permanently if you experience serious side effects during your treatment. This depends on how well the medication works for you and the side effects you experience. Talk to your doctor about how you are feeling during your treatment. Continue to take idelalisib even if you feel well. Do not stop taking idelalisib without talking to your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking idelalisib,

• tell your doctor and pharmacist if you are allergic to idelalisib, any other medications, or any of the ingredients in idelalisib tablets. If you have ever had a severe allergic reaction in the past, such as swelling of your face, lips or throat; difficulty swallowing or breathing; or peeling, blistering skin, your doctor will probably tell you not to take idelalisib.Ask your pharmacist or check the Medication Guide for a list of the ingredients.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: carbamazepine (Carbatrol, Epitol, Equetro, others); clarithromycin (Biaxin, in PrevPac); itraconazole (Onmel, Sporanox); ketoconazole (Nizoral); medications used to treat human immunodeficiency virus (HIV) such as efavirenz (Sustiva, in Atripla), indinavir (Crixivan), nelfinavir (Viracept), nevirapine (Viramune), ritonavir (Norvir, in Kaletra, in Technivie); midazolam; nefazodone; phenobarbital; phenytoin (Dilantin, Phenytek); pioglitazone (Actos, in Actoplus Met, in Duetact, in Oseni); rifabutin (Mycobutin); and rifampin (Rifadin, Rimactane, in Rifamate, in Rifater). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with idelalisib, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
• tell your doctor and pharmacist what herbal products you are taking, especially St. John’s wort. You should not take St. John’s wort during your treatment with idelalisib.
• tell your doctor if you are pregnant, plan to become pregnant, or plan to father a child. You should not become pregnant during your treatment with idelalisib. You should use birth control to prevent pregnancy during your treatment with idelalisib and at least 1 month after your final dose. If you are a male and your partner can become pregnant, you should use effective birth control during your treatment and for 3 months after your final dose. If you or your partner become pregnant while taking idelalisib, call your doctor immediately. Idelalisib may harm the fetus.
• tell your doctor if you are breastfeeding. You should not breastfeed while you are taking idelalisib and for at least one month after your final dose.

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medication.

If you miss a dose of idelalisib by less than 6 hours, take the missed dose as soon as you remember it and then take the next dose at the scheduled time. However, if you miss a dose by more than 6 hours, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Idelalisib may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• headache
• difficulty falling asleep or staying asleep
• decreased appetite
• increased thirst
• heartburn
• joint pain
• night sweats
• lack of energy
• swelling of the hands, feet, ankles, or lower legs

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:

• red, itching, peeling, or blistering skin
• painful sores or ulcers on your skin, lips, or in your mouth
• difficulty swallowing or breathing; swelling of the face, lips, or throat; hives; itching

Idelalisib may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA’s Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

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