Gefitinib | Side Effects, Dosage, Uses & More
Advertisement

Generic Name:

gefitinib, Oral tablet

All Brands

  • Iressa
SECTION 1 of 5

Highlights for gefitinib

Oral tablet
1

Gefitinib is used to treat a type of lung cancer called non-small cell lung cancer (NSCLC). This drug is only used if this type of cancer has certain genetic markers and has spread to other parts of your body.

2

This drug comes as a tablet you take by mouth.

3

Gefitinib is available as the brand-name drug Iressa. It isn’t available as a generic drug.

4

The more common side effects of this drug include skin reactions, diarrhea, decreased appetite, vomiting, mouth sores, and eyes that are red, itchy, or dry.

5

In some cases, gefitinib can cause serious side effects. These can include lung or breathing problems, liver problems, or a tear in the wall of your stomach or intestines. They also include severe diarrhea, eye problems, or severe skin reactions.

IMPORTANT INFORMATION

Lung disease

Gefitinib may cause a lung disease that could lead to death. Symptoms of this lung disease may be similar to symptoms of lung cancer. Tell your doctor right away if you have any new or worsening symptoms of lung problems, including trouble breathing, shortness of breath, cough, or fever.

Liver damage

Gefitinib may cause liver damage that could lead to death. Tell your doctor right away if you have any symptoms of liver damage, such as yellowing of your skin or the whites of your eyes, dark or brown urine, light-colored stools, decreased appetite, or pain on the right side of your stomach.

Stomach or intestinal wall perforation

This drug may cause a perforation (a tear or hole) in the wall of your stomach or intestines. Get emergency medical help right away if you have severe stomach pain.

Skin reactions

This drug can cause skin redness, rash, itching, and acne. This may occur on any part of your body. Get medical help right away if you develop severe skin reactions such as peeling or blistering.

What is gefitinib?

Gefitinib is a prescription drug. It comes as a tablet you take by mouth. It is available as the brand-name drug Iressa. It is not available as a generic drug.

Gefitinib may be used as part of a combination therapy. This means you may need to take it with other medications.

Why it's used

Gefitinib is used to treat non-small cell lung cancer that has spread to other parts of your body and has abnormal epidermal growth factor receptor genes. These abnormal genes promote the growth of cancer cells.

How it works

Gefitinib belongs to a class of drugs called kinase inhibitors. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

See Details

How it works

Gefitinib belongs to a class of drugs called kinase inhibitors. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

Gefitinib works by stopping the activity of certain receptor genes on cancer cells. This stops the cancer cells from growing and spreading.

Advertisement
SECTION 2 of 5

gefitinib Side Effects

Oral tablet

More common side effects

The more common side effects of gefitinib can include:

  • skin reactions

  • diarrhea

  • decreased appetite

  • vomiting

  • mouth sores

  • red, itchy, or dry eyes

If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 9-1-1 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

  • Lung or breathing problems. Symptoms can include:

    • trouble breathing
    • shortness of breath
    • cough
    • fever
  • Liver problems. Symptoms can include:

    • yellowing of your skin or the whites of your eyes
    • dark or brown (tea-colored) urine
    • light-colored stools
    • decreased appetite
    • pain on the right side of your stomach
  • Tear in the wall of your stomach or intestines. Symptoms can include:

    • severe stomach pain
  • Severe diarrhea or diarrhea that won't go away

  • Eye problems. Symptoms can include:

    • watery eyes
    • sensitivity to light
    • blurred vision
    • eye pain
    • eye redness
    • vision changes
  • Skin reactions. Symptoms can include:

    • peeling skin
    • blistering skin
    • rash
Pharmacist's Advice
Heathline Pharmacist Editorial Team

Gefitinib may cause problems with fertility (ability to get pregnant) in women. Talk to your doctor if you plan to become pregnant.

Gefitinib doesn’t cause drowsiness.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.
SECTION 3 of 5

gefitinib May Interact with Other Medications

Oral tablet

Gefitinib can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Food interactions

Grapefruit and grapefruit juice may increase the amount of gefitinib in your body. This may increase your risk of side effects such as skin reactions, diarrhea, vomiting, decreased appetite, or mouth sores. Small amounts of grapefruit and grapefruit juice are ok, but avoid having large amounts or having it too often.

Medications that might interact with this drug

Interactions that increase your risk of side effects
  • Increased side effects from other drugs: Taking gefitinib with certain medications raises your risk of side effects from these drugs. Examples of these drugs include:
    • Warfarin
      • Increased side effects can include bleeding. If you take warfarin with gefitinib, your doctor should check your blood regularly to see how fast it clots.
  • Increased side effects from gefitinib: Taking gefitinib with certain medications raises your risk of side effects from gefitinib. This is because the amount of gefitinib in your body is increased. Examples of these drugs include:
    • Ketoconazole and itraconazole
      • Increased side effects can include skin reactions, diarrhea, vomiting, decreased appetite, or mouth sores. You and your doctor should watch for side effects.

Interactions that can make gefitinib less effective
  • When gefitinib is less effective: When gefitinib is used with certain drugs, it may not work as well to treat your condition. This is because the amount of gefitinib in your body is decreased. Examples of these drugs include:
    • Phenytoin, rifampicin, doxepin, imipramine, amitriptyline, nortriptyline, and desipramine
      • These drugs may decrease the amount of gefitinib in your body. Your doctor may increase your dose of gefitinib while you are taking any of these drugs.
    • Antacids, famotidine, ranitidine, lansoprazole, pantoprazole, omeprazole, and esomeprazole
      • These drugs may prevent your body from absorbing gefitinib. You should avoid taking any of these drugs with gefitinib if you can. Talk to your doctor about the best time to take these drugs during your treatment with gefitinib. You may need to take gefitinib 6–12 hours before or after taking these drugs.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.
Gefitinib warnings
liver disease warning
People with liver disease

If you have liver disease, you may not be able to clear this drug from your body very well. This may increase the levels of gefitinib in your body and cause more side effects. Your doctor will watch for more side effects if you have mild or moderate liver disease. If you have severe liver disease, you should not use this drug.

lung disease warning
People with lung disease

If you have a history of lung disease, such as asthma or chronic obstructive pulmonary disease, you may be at increased risk of breathing-related side effects and complications from gefitinib. Talk to your doctor to see if this drug is safe for you.

pregnancy warning
Pregnant women

The Food and Drug Administration (FDA) hasn’t assigned a pregnancy category to gefitinib. Gefitinib can harm your fetus. If you are a woman of childbearing age, you should use an effective method of birth control during your treatment with gefitinib and for at least 2 weeks after your last dose. You should avoid becoming pregnant during treatment with gefitinib. Tell your doctor right away if you do become pregnant during treatment.

breast feeding warning
Women who are breast-feeding

It is not known if gefitinib passes into breast milk. It may cause side effects in a child who is breastfed.

Do not breastfeed your child during your treatment with gefitinib. Talk to your doctor about the best way to feed your child during this time.

childrens warning
For children

It is not known if gefitinib is safe and effective for use in children. Do not use gefitinib in children younger than 18 years.

call the doctor
When to call the doctor

Call your doctor right away if you become pregnant while taking this drug.

allergy warning
Allergies

Gefitinib can cause a severe allergic reaction. Symptoms can include:

  • trouble breathing
  • swelling of your throat or tongue
  • hives (skin rash with red, raised, itchy bumps)

If you have an allergic reaction, call your doctor or local poison control center right away. If your symptoms are severe, call 9-1-1 or go to the nearest emergency room.

Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).

SECTION 4 of 5

How to Take gefitinib (Dosage)

Oral tablet

All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:

  • your age
  • the condition being treated
  • how severe your condition is
  • other medical conditions you have
  • how you react to the first dose

What are you taking this medication for?

Metastatic non-small cell lung cancer

Brand: Iressa

Form: Oral tablet
Strengths: 250 mg
Adult dosage (ages 18 years and older)

The typical dose is 250 mg taken once per day.

Child dosage (ages 0–17 years)

It is not known if gefitinib is safe and effective in children. It should not be used in people younger than 18 years.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always to speak with your doctor or pharmacist about dosages that are right for you.
Pharmacist's Advice
Healthline Pharmacist Editorial Team

Gefitinib comes with risks if you don’t take it as prescribed.

If you stop taking the drug suddenly or don’t take it at all

Your lung cancer may not get better and may get worse.

If you miss doses or don’t take the drug on schedule

Your medication may not work as well or may stop working completely. For this drug to work well, a certain amount needs to be in your body at all times.

If you take too much

You could have dangerous levels of the drug in your body. If you think you’ve taken too much of this drug, call your doctor or local poison control center. If your symptoms are severe, call 9-1-1 or go to the nearest emergency room right away.

What to do if you miss a dose

Take the dose as soon as you remember. If it is less than 12 hours until your next dose, take only your next dose at its regular time. Never try to catch up by taking two doses at once. This could result in dangerous side effects.

How to tell if the drug is working

You may not be able to tell if the drug is working, but your doctor will perform tests to check how your cancer is responding to treatment with this drug.

Gefitinib is used for short-term treatment.

Ask your doctor if you can cut or crush the tablet

Gefitinib tablets have a coating and are not easy to cut in half.

If you cannot swallow the tablets whole, place your dose in a container with 4–8 oz of water and stir for 15 minutes. Drink the mixture right away. Put another 4–8 oz of water in the same container and drink that right away.

Store this drug carefully

  • Store gefitinib at room temperature between 68°F and 77°F (20°C and 25°C).
  • Don’t store this medication in moist or damp areas, such as bathrooms.
  • Keep this drug out of reach of children.

A prescription for this medication is refillable

You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.

Travel

When traveling with your medication:

  • Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
  • Don’t worry about airport x-ray machines. They can’t hurt your medication.
  • You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled box with you.
  • Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.

Clinical monitoring

Your doctor should monitor certain health issues. This can help make sure you stay safe while you take this drug. These issues include:

  • Liver function. Your doctor will do blood tests to check your liver function during your treatment with gefitinib.

Your diet

You should limit how much grapefruit or grapefruit juice you have during your treatment. Having grapefruit often or in large amounts while you take this drug increases your risk of side effects.

Not every pharmacy stocks this drug

When filling your prescription, be sure to call ahead.

Insurance

Many insurance companies require a prior authorization for this drug. This means your doctor may need to get approval from your insurance company before your insurance company will pay for the prescription.

Are there any alternatives?

There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.

What does the pill look like?

Showing - out of 2
SECTION 5 of 5

How Much Does gefitinib Cost?

Oral tablet

We've partnered with GoodRx so you can compare prices, find discounts and save up to 80% on your next prescription. Check out the low coupon prices below — no insurance required.

Compare prices and save up to 80% on your next refill!

Lowest price for gefitinib

Membership warehouse $7,214.96
Kroger Pharmacy $7,236.76
Target (CVS) $7,410.78
These prices represent the lowest priced national pharmacies for gefitinib on GoodRx. They may be lower than your insurance.

Enter your zip code to find the best deal near you.

These prices represent the lowest priced national pharmacies for gefitinib on GoodRx. They may be lower than your insurance.

Show Sources

Content developed in collaboration with University of Illinois-Chicago, Drug Information Group

Medically reviewed by Creighton University, Center for Drug Information and Evidence-Based Practice on February 9, 2016

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.
Advertisement
Advertisement
Advertisement