Imatinib

WHY is this medicine prescribed?

Imatinib is used to treat:

• certain types of leukemia(cancer that begins in the white blood cells) and other cancers and disorders of the blood cells
• certain types of gastrointestinal stromal tumors(GIST; a type of tumor that grows in the walls of the digestive passages and may spread to other parts of the body)
• certain types of dermatofibrosarcoma protuberans (a tumor that forms under the top layer of skin)

Imatinib is in a class of medications called kinase inhibitors. It works by blocking the action of an abnormal protein in cancer cells. This helps slow or stop the spread of cancer cells.

Are there OTHER USES for this medicine?

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

HOW should this medicine be used?

Imatinib comes as a tablet and a solution (liquid) to take by mouth.Take with a meal and a large glass of water once or twice a day. Take imatinib at around the same time(s) every day.

Take imatinib exactly as directed. Ask your doctor or pharmacist to explain any part you do not understand. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not chew or crush them. If you touch or come into direct contact with a crushed tablet, wash the area thoroughly.

If you are unable to swallow imatinib tablets whole, place all of the tablets that you need for one dose into a glass of water or apple juice. Use 50 milliliters (a little less than 2 ounces) of liquid for each 100-mg tablet and 200 milliliters (a little less than 7 ounces) of liquid for each 400-mg tablet. Stir with a spoon until the tablets crumble completely and drink the mixture immediately.

If you are taking imatinib solution, do not use a household spoon to measure your dose. Always use the bottle adapter and measuring syringe that comes with your medication. You may not receive the correct amount of medication if you use a household spoon to measure your dose. Wear disposable gloves when you prepare, take, or give imatinib solution. Read the instructions for use before you start taking imatinib solution and ask your pharmacist if you have any questions.

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

What SPECIAL PRECAUTIONS should I follow?

Before taking imatinib,

• tell your doctor and pharmacist if you are allergic to this drug, any part of this drug, or anyother drugs, food, or substances. Tell your doctor or pharmacist about the allergy and whatsymptoms you had.

• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking imatinib. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• the following nonprescription and herbal products may interact with imatinib: St. John's wort and iron supplements. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking imatinib. Do not start these medications while taking imatinib without discussing with your healthcare provider.

• tell your doctor if you have or have ever had diabetes, high blood pressure, heart failure or other heart problems, or lung, thyroid, kidney, or liver disease.

• tell your doctor if you are pregnant or plan to become pregnant. You may have to take a pregnancy test before starting treatment, You should not become pregnant while you are taking imatinib and for 14 days after your final dose. Talk to your doctor about birth control methods that you can use during your treatment. If you become pregnant while taking imatinib, call your doctor. Imatinib may harm the fetus.

• tell your doctor if you are breastfeeding. You should not breastfeed while you are taking imatinib and for one month after your final dose.

• you should know that imatinib may make you dizzy, drowsy, or cause blurred vision. Do not drive a car or operate machinery until you know how this medication affects you.

What SPECIAL DIETARY instructions should I follow?

Do not eat grapefruit or drink grapefruit juice while taking this medication.

What should I do IF I FORGET to take a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What SIDE EFFECTS can this medicine cause?

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

• diarrhea
• nausea
• vomiting
• change in the way things taste
• mouth sores or swelling inside the mouth
• loss of appetite
• weight loss
• heartburn or indigestion
• dry mouth
• headache
• joint swelling or pain
• bone pain
• muscle cramps, spasms, or pain
• tingling, burning. or prickling feeling on the skin
• difficulty falling asleep or staying asleep
• sweating
• red or teary eyes
• flushing
• dry skin
• rash
• itching
• nail changes
• hair loss

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately:

• swelling of the face, eyes, hands, feet, ankles, or lower legs; sudden weight gain; shortness of breath; fast, irregular, or pounding heartbeat
• decreased urination
• chest pain
• peeling, blistering, or shedding skin
• yellowing of the skin or eyes, loss of appetite, fatigue, pain in the upper right part of the stomach, nausea, vomiting, or flu-like symptoms
• unusual bruising or bleeding; bloody, black, or tarry stools; coughing up or vomiting blood or material that looks like coffee grounds; or nosebleed
• flu-like symptoms, sore throat, fever, chills, and other signs of infection
• excessive tiredness or weakness
• abdominal pain or bloating

Imatinib may slow growth in children. Your child's doctor will watch his or her growth carefully. Talk to your child's doctor about the risks of giving imatinib to your child.

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

What should I know about STORAGE and DISPOSAL of this medication?

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 excess heat and moisture (not in the bathroom).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reachhttps://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

What should I do in case of OVERDOSE?

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.

Symptoms of overdose may include the following:

• nausea
• vomiting
• diarrhea
• rash
• swelling
• extreme tiredness
• muscle cramps or spasms
• abdominal pain
• headache
• loss of appetite

What OTHER INFORMATION should I know?

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

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

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.