Imatinib

Imatinib is used to treat certain types of leukemia (cancer that begins in the white blood cells) and other cancers of the blood cells. Imatinib is also used to treat 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). Imatinib is also used to treat dermatofibrosarcoma protuberans (a tumor that forms under the top layer of skin) when the tumor cannot be removed surgically, has spread to other parts of the body, or has come back after surgery. Imatinib is in a class of medications called protein-tyrosine 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.

Imatinib comes as a tablet to take by mouth. It is usually taken with a meal and a large glass of water once or twice a day. Take imatinib at around the same time(s) 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 imatinib exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. If you are unable to swallow imatinib tablets, you may 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 100 milliliters (a little less than 4 ounces) of liquid for each 400-mg tablet. Stir with a spoon until the tablets crumble completely and drink the mixture immediately. If your doctor has told you to take 800 mg of imatinib, you should take 2 of the 400-mg tablets. Do not take 8 of the 100-mg tablets. The tablet coating contains iron, and you will receive too much iron if you take 8 of the 100-mg tablets. 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.

<p></p> <p></p> <p></p> <p>Imatinib may cause side effects. Inform your doctor if any of these symptoms are severe or do not go away:

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diarrhea</li>
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constipation</li>
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gas</li>
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nausea</li>
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vomiting</li>
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loss of appetite</li>
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indigestion</li>
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joint pain</li>
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muscle cramps</li>
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depression</li>
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anxiety</li>
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night sweats</li>
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teary eyes</li></ul></p> <p></p> <p>Some side effects can be serious. If you experience any of these symptoms call your doctor immediately:

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puffiness under the eyes</li>
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swelling of the hands, feet, ankles, or lower legs</li>
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weight gain</li>
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shortness of breath</li>
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fast, irregular, or pounding heartbeat</li>
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difficulty falling asleep or staying asleep</li>
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fainting</li>
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coughing up pink or bloody mucus</li>
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increased urination, especially at night</li>
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chest pain</li>
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fever</li>
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rash or blisters</li>
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yellowing of the skin or eyes</li>
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blood in the stool</li>
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unusual bruising or bleeding</li>
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sore throat, fever, chills, and other signs of infection</li>
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excessive tiredness or weakness</li>
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headache</li>
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dizziness</li></ul>Imatinib may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.</p>

Before taking imatinib, tell your doctor and pharmacist if you are allergic to imatinib or any other medications. tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: acetaminophen (Tylenol); certain antibiotics including erythromycin (E.E.S., E-Mycin, Erythrocin), clarithromycin (Biaxin), and rifampin (Rifadin, in Rifamate); anticoagulants ('blood thinners') such as warfarin (Coumadin); antifungals such as ketoconazole (Nizoral) and itraconazole (Sporanox); calcium channel blockers such as amlodipine (Norvasc, in Caduet), diltiazem (Cardizem, Tiazac), felodipine (Plendil), isradipine (Dynacirc), nicardipine (Cardene), nifedipine (Adalat, Procardia, others), nimodipine (Nimotop), nisoldipine (Sular), or verapamil (Calan, Covera, Isoptin, Verelan); cholesterol-lowering medications (statins) such as atorvastatin (Lipitor), lovastatin (Mevacor), and simvastatin (Zocor); cyclosporine (Neoral, Sandimmune); dexamethasone; hormonal contraceptives (birth control pills, patches, rings, injections or implants); pimozide (Orap); medications for anxiety; medications for seizures such as carbamazepine (Tegretol), phenobarbital, and phenytoin (Dilantin); sedatives; sleeping pills; and tranquilizers. Other medications may also interact with imatinib, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. tell your doctor what herbal products you are taking, especially St. John's wort. tell your doctor if you have or have ever had high blood pressure; a heart attack; an irregular heartbeat; diabetes; or heart, lung, thyroid, or liver disease. Also tell your doctor if you smoke, if you use street drugs, and if you drink or have ever drunk large amounts of alcohol. talk to your doctor about what you should do if you develop diarrhea during your treatment. Do not take any medications to treat diarrhea without talking to your doctor.

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911. Symptoms of overdose may include:

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muscle cramps</li>
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swollen or bloated stomach</li></ul>