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Generic Name: gefitinib (ge FI ti nib)
Brand Name: Iressa

What is gefitinib?

Gefitinib is a cancer medication that interferes with the growth and spread of cancer cells in the body.

Gefitinib is used in to treat non-small cell lung cancer.

Gefitinib is sometimes used to treat cancer that has spread to other parts of the body.

Gefitinib may also be used for purposes not listed in this medication guide.

What is the most important information I should know about gefitinib?

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

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What should I discuss with my healthcare provider before taking gefitinib?

You should not use gefitinib if you are allergic to it.

To make sure gefitinib is safe for you, tell your doctor if you have:

  • liver disease;

  • kidney disease;

  • vision problems;

  • breathing problems, lung disease other than lung cancer; or

  • if you take a blood thinner (warfarin, Coumadin, Jantoven).

Do not use gefitinib if you are pregnant. It could harm the unborn baby. Use effective birth control to prevent pregnancy while you are using this medicine and for at least 2 weeks after your treatment ends.

This medicine may affect fertility (the ability to have children) in women. Tell your doctor if you plan to become pregnant.

It is not known whether gefitinib passes into breast milk or if it could harm a nursing baby. Do not breast-feed while taking gefitinib.

How should I use gefitinib?

Your doctor will perform blood tests to make sure you have the correct tumor type to be treated with gefitinib.

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use this medicine in larger or smaller amounts or for longer than recommended.

You may take gefitinib with or without food.

To make swallowing easier:

  • Place the tablet into a glass of water (4 to 8 ounces) and stir for about 15 minutes.

  • Do not use any liquid other than water.

  • Stir and drink this mixture right away. Do not save for later use.

  • To make sure you get the entire dose, add 4 to 8 more ounces of water to the same glass, swirl gently and drink right away.

  • This mixture may also be given through a nasogastric (NG) tube. Ask your healthcare provider for instructions.

While using gefitinib, you may need frequent blood tests to check your liver function.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if your next dose is less than 12 hours away. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using gefitinib?

Avoid taking an antacid or stomach acid reducer (Nexium, Pepcid, Prevacid, Prilosec, Zantac, and others) within 6 hours before or 6 hours after you take gefitinib. These other medicines can make gefitinib much less effective when taken at the same time.

Gefitinib side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • severe or ongoing diarrhea;

  • sudden chest pain or discomfort, new or worsening cough with fever, trouble breathing;

  • blurred vision, watery eyes, eye pain or redness, eyes being more sensitive to light;

  • liver problems--nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);

  • signs of stomach bleeding--severe stomach pain, bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds; or

  • severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common side effects may include:

  • diarrhea;

  • acne;

  • dry skin; or

  • itching or skin rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

Gefitinib dosing information

Usual Adult Dose for Non-Small Cell Lung Cancer:

250 mg orally once a day

Duration of therapy: Until disease progression or unacceptable toxicity

-Information on FDA-approved tests for detection of EGFR mutations in NSCLC:

Use: First-line treatment of metastatic non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations as detected by an FDA-approved test.

What other drugs will affect gefitinib?

Other drugs may interact with gefitinib, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your doctor or pharmacist can provide more information about gefitinib.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 3.02. Revision Date: 2015-09-14, 10:02:26 PM.