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Generic Name: gefitinib (geh-FIT-in-ib)
Brand Name: Iressa

Iressa is used for:

Treating non-small cell lung cancer after other cancer chemotherapy treatments have not been successful. It may also be used for other conditions as determined by your doctor.

Iressa is a cancer chemotherapy agent. It works by blocking a certain protein (an enzyme called tyrosine kinase). This helps to stop the cancer from growing and spreading.

Do NOT use Iressa if:

  • you are allergic to any ingredient in Iressa

Contact your doctor or health care provider right away if any of these apply to you.

Before using Iressa:

Some medical conditions may interact with Iressa. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have lung disease (eg, pulmonary fibrosis), heart problems, severe kidney problems, or liver problems
  • if you have had a stroke

Some MEDICINES MAY INTERACT with Iressa. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Antacids (eg, sodium bicarbonate, calcium carbonate), histamine H2-receptor blockers (eg, famotidine), hydantoins (eg, phenytoin), or rifampin because the effectiveness of Iressa may be decreased
  • Imidazoles (eg, ketoconazole) because the side effects of Iressa may be increased
  • Anticoagulants (eg, warfarin) because the risk of bleeding may be increased
  • Vinorelbine because the risk of low white blood cell counts may be increased

This may not be a complete list of all interactions that may occur. Ask your health care provider if Iressa may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Iressa:

Use Iressa as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Iressa may be taken with or without food.
  • If you have difficulty swallowing the tablet, it can be added to half a glass of water (non-carbonated). Do not use other liquids. Drop the tablet into the water, without crushing it, and stir until it dissolves (about 10 minutes). Then drink the liquid immediately. Rinse the glass with half a glass of water and drink it.
  • Take Iressa regularly to receive the most benefit from it.
  • Taking Iressa at the same time each day will help you remember to take it.
  • If you miss a dose of Iressa, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Iressa.

Important safety information:

  • Additional monitoring of your dose or condition may be needed if you are taking erythromycin, clarithromycin, or St. John's wort.
  • Iressa may cause changes in vision. Contact your doctor if eye irritation occurs. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Iressa.
  • LAB TESTS, including liver function tests, may be performed to monitor your progress or to check for side effects. Be sure to keep all doctor and lab appointments.
  • Iressa is not recommended for use in CHILDREN. Safety and effectiveness have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: Do not become pregnant while taking Iressa. Iressa may cause harm to the fetus. If you become pregnant, discuss with your doctor the benefits and risks of using Iressa during pregnancy. It is unknown if Iressa is excreted in breast milk. Do not breast-feed while taking Iressa.

Possible side effects of Iressa:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Acne; diarrhea; dry skin; loss of appetite; mouth ulcers; nausea; unusual weakness; vision problems; vomiting; weight loss.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the eyelids, mouth, face, lips, or tongue); cough; dark urine; dizziness; eye irritation or pain; extreme fatigue; fever; persistent diarrhea; stomach pain; swelling of the ankles or feet; yellowing of the skin or eyes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include severe or persistent diarrhea; severe skin rash.

Proper storage of Iressa:

Store Iressa at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Iressa out of the reach of children and away from pets.

General information:

  • If you have any questions about Iressa, please talk with your doctor, pharmacist, or other health care provider.
  • Iressa is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information is a summary only. It does not contain all information about Iressa. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

Review Date: October 1, 2016

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.