Common Brand Name(s): Iressa
Important: How To Use This Information
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.
Gefitinib has rarely caused very serious (possibly fatal) liver disease. Get medical help right away if you develop symptoms of liver disease, including stomach/abdominal pain, extreme fatigue, dark urine, yellowing eyes/skin.
Gefitinib has also rarely caused very serious (possibly fatal) holes in the wall of the stomach or intestines. Get medical help right away if you develop stomach/abdominal pain, black/bloody stools, or vomit that looks like coffee grounds.
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).
How To Use
Read the Patient Information Leaflet if available from your pharmacist before you start taking gefitinib and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take gefitinib by mouth with or without food as directed by your doctor, usually once daily.
If you have trouble swallowing the tablet, you may place the tablet in a glass of water (4 to 8 ounces/120 to 240 milliliters). Stir well for 15 minutes. Drink all of the mixture right away. Rinse the cup with another 4 to 8 ounces (120 to 240 milliliters) of water and drink the rinse water to make sure you get the full dose.
Medications which reduce or block stomach acid (such as proton pump inhibitors/PPIs, H2 blockers, antacids) may reduce the absorption of gefitinib, making it work less well. If you take PPIs (such as omeprazole, lansoprazole), take gefitinib at least 12 hours before or 12 after the PPI. If you take antacids or H2 blockers (such as famotidine, ranitidine), take them at least 6 hours before or at least 6 hours after this medication.
The dosage is based on your medical condition, response to treatment, lab tests, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.
Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of side effects will increase.
See also Warning section.
Diarrhea, rash, acne, nausea, vomiting, loss of appetite, nail problems, hair loss, red/sore mouth or throat, or unusual weakness may occur. If any of these effects persist or worsen, notify your doctor or pharmacist right away.
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
Tell your doctor right away if any of these unlikely but serious side effects occur:
- unusual bleeding (coughing up blood, blood in urine)
- eye irritation/pain
- swelling of the ankles/feet
Gefitinib may cause rare (possibly fatal) lung disease (interstitial lung disease-ILD). Tell your doctor right away 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)
- 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 or at www.fda.gov/medwatch.
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 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
- stomach/intestinal ulcers
- other stomach/intestinal problems (such as diverticulitis, blockage, bowel disease)
- cancer that has spread to the bowels
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using gefitinib. Gefitinib may harm an unborn baby. Ask about reliable forms of birth control while using this medication and for 2 weeks after stopping treatment. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.
It is unknown if this drug passes into breast milk. Because of possible risk to the infant, breast-feeding while using gefitinib is not recommended. Consult your doctor before breast-feeding.
See also How to Use section.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug are:
- "blood thinners" (warfarin)
- drugs which reduce stomach acid (e.g., ranitidine, cimetidine, famotidine, omeprazole, lansoprazole, rabeprazole)
- NSAIDs (such as ibuprofen, naproxen)
- corticosteroids (such as prednisone)
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe/persistent diarrhea, severe skin rash.
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.
If you miss a dose, take it as soon as you remember. If it is less than 12 hours before the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
Store at room temperature away from light and moisture. 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.
Information last revised March 2019.
Copyright(c) 2019 First Databank, Inc.
Conditions of use: The information in this database is intended to supplement, not substitute for the expertise and judgment of healthcare professionals. The information in not intend to cover all possible uses, directions, precautions, drug interactions or adverse effects nor should it be construed in indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.