This medication is used to treat certain types of cancer (e.g., chronic myeloid leukemia, gastrointestinal stromal tumors, and myelodysplastic/myeloproliferative diseases). Imatinib works by stopping or slowing the growth of cancer cells (tumors). It also works by causing cancer cells to die.

How to use imatinib Oral
Take this medication by mouth with a meal and a full glass of water (8 ounces or 240 milliliters), usually once or twice daily or as directed by your doctor. The US manufacturer recommends that if you have trouble swallowing the tablets whole, you may dissolve your dose in a glass of water or apple juice. The amount of liquid will vary depending on your dose. Consult your doctor or pharmacist for more detailed instructions. Stir the mixture well until the tablet(s) dissolve, and drink immediately.
The dosage is based on your medical condition and response to therapy. Do not increase your dose or take this medication more often than prescribed. Your condition will not improve any faster, and the risk of serious side effects may be increased.
Since this drug can be absorbed through the skin and lungs, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

Upset stomach, nausea, vomiting, diarrhea, headache, joint pain, or muscle cramps/pain may occur. If any of these effects persist or worsen, notify your doctor.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these unlikely but serious side effects occur: easy bruising/bleeding, fast/pounding heartbeat, extreme tiredness, sudden/unexplained weight gain, swelling (especially of lower legs/the area around eyes), increasing trouble breathing (shortness of breath).
Tell your doctor immediately if any of these rare but very serious side effects occur: black/bloody stools, dark urine, stomach/abdominal pain, vomit that looks like coffee grounds, yellowing eyes/skin.
This medication can lower the body\'s ability to fight an infection. Notify your doctor promptly if you develop any signs of an infection such as fever, chills, or persistent sore throat.
Imatinib sometimes causes side effects due to the rapid destruction of cancer cells (tumor lysis syndrome). To lower your risk, drink plenty of fluids unless your doctor directs you otherwise. Tell your doctor immediately if you experience symptoms such as low back/side pain (flank pain), red/pinkish urine, painful urination, or muscle spasms/weakness.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice any other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking imatinib, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: bleeding problems, heart problems (e.g., heart failure), kidney problems, liver problems.
Do not have immunizations/vaccinations without the consent of your doctor, and avoid contact with people who have recently received oral polio vaccine or flu vaccine inhaled through the nose. Wash your hands well to prevent the spread of infections.
To lower your risk of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.
Before having surgery, tell your doctor or dentist that you are using this medication.
This medication may slow down a child\'s growth. The effect on final adult height is unknown. See the doctor regularly so your child\'s height can be checked.
The elderly may be more sensitive to the side effects of this drug (e.g., swelling). Also, the manufacturer recommends a routine heart test (LV ejection fraction) in the elderly before treatment.
This medication is not recommended for use during pregnancy. It may harm the unborn baby. If you become pregnant or think you may be pregnant, inform your doctor immediately. To avoid pregnancy, both males and females using this drug must use reliable form(s) of birth control (e.g., condoms, birth control pills) during treatment with this drug. Talk with your doctor about effective forms of birth control.
This medication passes into breast milk. Because of possible risk to the infant, breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding.

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.
This drug should not be used with the following medication because very serious interactions may occur: warfarin.
If you are currently using the medication listed above, tell your doctor or pharmacist before starting imatinib.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: levothyroxine, drugs affecting liver enzymes that remove imatinib from your body (such as azole antifungals including itraconazole/ketoconazole, HIV protease inhibitors including ritonavir/saquinavir, macrolide antibiotics including erythromycin, cimetidine, rifamycins including rifampin/rifabutin, corticosteroids including dexamethasone, St. John\'s wort, certain anti-seizure medicines including carbamazepine/phenytoin).
This drug can slow down the removal of other drugs from your body by affecting certain liver enzymes. These affected drugs include acetaminophen, cyclosporine, midazolam, nifedipine, sildenafil, and simvastatin, among others. Ask your doctor about using these drugs safely.
Check the labels on all your medicines because they may contain acetaminophen. Ask your pharmacist about using those products safely.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

If overdose is suspected, contact your local poison control center or emergency room immediately. US residents should call the US National Poison Hotline at 1-800-222-1222. Canada residents should call a provincial poison control center. Symptoms of overdose may include: severe muscle cramps, dark urine, abdominal swelling.

NOTES:
Do not share this medication with others.
Laboratory and/or medical tests (e.g., complete blood count, liver function tests) should be performed to monitor your progress or check for side effects. Consult your doctor for more details.

MISSED DOSE:
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

STORAGE:
Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
MEDICAL ALERT: Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-800-854-1166 (USA) or 1-800-668-1507 (Canada).
Information last revised November 2011. Copyright(c) 2011 First Databank, Inc.