GEFITINIB - ORAL
Common Brand Name(s): Iressa
Phonetic Pronunciation: (geh-FIT-ih-nib)
Information last revised May 2010
What does GEFITINIB - ORAL look like?

IRESSA 250 mg Tab
Uses:
Gefitinib is used to treat lung cancer. It works by slowing or stopping the growth of cancer cells. Gefitinib blocks a certain protein (an enzyme called tyrosine kinase).
Missed Dose
If you miss a dose, use it as soon as you remember. If it is less than 12 hours before the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
How To Use
Take gefitinib by mouth once daily, with or without food, or as directed. Medications which reduce or completely block stomach acid (e.g., proton pump inhibitors/PPIs, H2 blockers, antacids) may decrease the absorption of gefitinib. This could decrease the effectiveness of gefitinib. Consult your doctor or pharmacist if you are taking any of these medications. Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may. Grapefruit may increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details. Use this medication regularly in order to get the most benefit from it. To help you remember, use it at the same time each day.
Drug Interactions
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. Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription products you may use, especially of: "blood thinners" (warfarin), drugs which reduce stomach acid (e.g., ranitidine, cimetidine, famotidine, omeprazole, lansoprazole, rabeprazole), certain liver enzyme inhibitors (CYP 3A4 inhibitors such as ketoconazole, itraconazole, erythromycin, clarithromycin), vinorelbine. Some liver enzyme inducer medications such as rifamycins (e.g., rifampin, rifabutin), St. John's wort or phenytoin will stimulate certain liver enzymes (CYP 3A4). Your dosage of gefitinib may need to be increased if you are using such medications. Consult your doctor or pharmacist for more details. 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.
Notes
Do not share this medication with others. Laboratory and/or medical tests (such as kidney/liver function tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
Overdose
If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US national poison hotline at 1-800-222-1222. Canadian residents should call their local poison control center directly. Symptoms of overdose may include: severe/persistent diarrhea, severe skin rash.
Precautions
Before taking this medication, 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: lung disease (e.g., pulmonary fibrosis), severe kidney disease, eye problems. Gefitinib is not recommended for use during pregnancy. It may cause harm to an unborn baby. Consult your doctor for more details. It is not known whether this drug passes into breast milk. Due to the potential risk to the infant, breast-feeding while using gefitinib is not recommended.
Storage
Store at room temperature between 68 and 77 degrees F (20-25 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines 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.
Side Effects
Diarrhea, rash, acne, nausea, vomiting, loss of appetite, red/sore mouth or throat, or unusual weakness may occur. If any of these effects persist or worsen, notify your doctor or pharmacist immediately. 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. Persistent nausea, vomiting, diarrhea, or loss of appetite may result in a serious loss of body water (dehydration) and kidney problems. Contact your doctor promptly if you notice any symptoms of dehydration, such as: unusual decreased urination, unusual dry mouth/thirst, fast heartbeat, dizziness/lightheadedness. Tell your doctor immediately if any of these unlikely but serious side effects occur: unusual bleeding (coughing up blood, blood in urine), bloody or black/tarry stool, eye irritation/pain, swelling of the ankles/feet. Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: stomach/abdominal pain, extreme fatigue, dark urine, yellowing eyes/skin. Gefitinib may cause rare (possibly fatal) lung disease (interstitial lung disease-ILD). Tell your doctor immediately if you develop trouble breathing, cough or fever. If you have persistent diarrhea or skin rashes contact your doctor. Your doctor may temporarily stop gefitinib (for up to 14 days) which may help reverse those side effects. Treatment is then resumed with the same dosage. An allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include: severe 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 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.
This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
The information contained in the First DataBank databases is intended to supplement the knowledge of physicians, pharmacists, and other healthcare professionals regarding drug therapy problems and patient counselling information. This information is advisory only and is not intended to replace sound clinical judgment in the delivery of healthcare services. First DataBank disclaims all warranties, whether expressed or implied, including any warranty as to the quality, accuracy, and suitability of this information for any purpose.
Copyright 2010 First DataBank, Inc.