Care During Chemotherapy and Beyond



Trade name: Iressa®

Drug type:  Gefitinib is a targeted therapy.  It is classified as a signal transduction inhibitor (epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor) - (For more detail, see "How this drug works," below.)

What Gefitinib Is Used For:

  • For the treatment of locally advanced or metastatic non-small cell lung cancer, after failure of both platinum-based and taxane-based chemotherapies.

Note:  If a drug has been approved for one use, physicians may elect to use this same drug for other problems if they believe it may be helpful.

How Gefitinib Is Given:

  • Gefitinib is a pill, taken by mouth, once daily.  It can be taken with or without food.
  • The amount of gefitinib that you will receive depends on many factors, your general health or other health problems, and the type of cancer or condition being treated.  Current recommendation is for one tablet daily, higher doses do not give a better response and may cause increased toxicity.  Your doctor will determine your dose and schedule.

Side Effects:

Important things to remember about the side effects of gefitinib:

  • Most people do not experience all of the side effects listed.
  • Side effects are often predictable in terms of their onset and duration.
  • Side effects are almost always reversible and will go away after treatment is complete.
  • There are many options to help minimize or prevent side effects.
  • There is no relationship between the presence or severity of side effects and the effectiveness of the medication.

The following side effects are common (occurring in greater than 30%) for patients taking gefitinib:

  • Diarrhea
  • Skin reaction (rash, acne)

These side effects are less common side effects (occurring in about 10-29%) of patients receiving gefitinib:

  • Nausea
  • Vomiting
  • Itching
  • Poor appetite
  • Eye irritation

Rare cases (about 1%) of a serious side effect of interstitial lung disease (pneumonia, or inflammation of the lungs without infection).  When this side effect occurred, it was often accompanied by breathing difficulty with cough or a low-grade fever requiring hospitalization.  1/3 of the cases had led to death.  If a sudden onset of shortness of breath, cough and/or fever occur while taking gefitinib, notify your health care professional.

Elevation in liver function tests (transaminase, bilirubin, and alkaline phosphatase) has been observed in patients treated with gefitinib.  These elevations were not accompanied by any symptoms of liver toxicity. However, your health care professional may check blood tests to monitor your liver function periodically, while you are taking gefitinib.

Not all side effects are listed above. Some that are rare (occurring in less than 10% of patients) are not listed here.  However, you should always inform your health care provider if you experience any unusual symptoms.

When to contact your doctor or health care provider:

Contact your health care provider immediately, day or night, if you should experience any of the following symptoms:

* Sudden onset of shortness of breath, accompanied by cough and/or fever.

The following symptoms require medical attention, but are not an emergency.  Contact your health care provider within 24 hours of noticing any of the following:

  • Diarrhea (4-6 episodes in a 24-hour period).
  • Nausea (interferes with ability to eat and unrelieved with prescribed medication).
  • Vomiting (vomiting more than 4-5 times in a 24 hour period).
  • Unable to eat or drink for 24 hours or have signs of dehydration: tiredness, thirst, dry mouth, dark and decrease amount of urine, or dizziness.
  • Eye irritation

Always inform your health care provider if you experience any unusual symptoms.


  • Before starting gefitinib treatment, make sure you tell your doctor about any other medications you are taking (including prescription, over-the-counter, vitamins, herbal remedies, etc.).   Do not take aspirin, or products containing aspirin unless your doctor specifically permits this.
  • Do not receive any kind of immunization or vaccination without your doctor's approval while taking gefitinib.
  • Inform your health care professional if you are pregnant or may be pregnant prior to starting this treatment. Pregnancy category D (gefitinib may be hazardous to the fetus.  Women who are pregnant or become pregnant must be advised of the potential hazard to the fetus.) 
  • For both men and women: Do not conceive a child (get pregnant) while taking gefitinib. Barrier methods of contraception, such as condoms, are recommended. Discuss with your doctor when you may safely become pregnant or conceive a child after therapy.
  • Do not breast feed while taking this medication.

Self-Care Tips:

  • Drink at least two to three quarts of fluid every 24 hours, unless you are instructed otherwise.
  • This medication causes little nausea.  But if you should experience nausea, take anti-nausea medications as prescribed by your doctor, and eat small frequent meals.  Sucking on lozenges and chewing gum may also help.
  • Avoid sun exposure.  Wear SPF 15 (or higher) sunblock and protective clothing.
  • In general, drinking alcoholic beverages should be kept to a minimum or avoided completely.  You should discuss this with your doctor.
  • Get plenty of rest. 
  • Maintain good nutrition.
  • If you experience symptoms or side effects, be sure to discuss them with your health care team.  They can prescribe medications and/or offer other suggestions that are effective in managing such problems.

Monitoring and Testing:

You will be checked regularly by your health care professional while you are taking gefitinib, to monitor side effects and check your response to therapy.

How Gefitinib Works:

Targeted therapy is the result of about 100 years of research dedicated to understanding the differences between cancer cells and normal cells.  To date, cancer treatment has focused primarily on killing rapidly dividing cells because one feature of cancer cells is that they divide rapidly.  Unfortunately, some of our normal cells divide rapidly too, causing multiple side effects. 

Targeted therapy is about identifying other features of cancer cells.  Scientists look for specific differences in the cancer cells and the normal cells.  This information is used to create a targeted therapy to attack the cancer cells without damaging the normal cells, thus leading to fewer side effects.  Each type of targeted therapy works a little bit differently but all interfere with the ability of the cancer cell to grow, divide, repair and/or communicate with other cells. 

There are different types of targeted therapies, defined in three broad categories.  Some targeted therapies focus on the internal components and function of the cancer cell.  The targeted therapies use small molecules that can get into the cell and disrupt the function of the cells, causing them to die.  There are several types of targeted therapy that focus on the inner parts of the cells.   Other targeted therapies target receptors that are on the outside of the cell.   Therapies that target receptors are also known as monoclonal antibodies.  Antiangiogenesis inhibitors target the blood vessels that supply oxygen to the cells, ultimately causing the cells to starve.

Genefitinib is a targeted therapy that targets and binds to the epidermal growth factor receptors (EGFR) on the surface of the cell. EGFR is found on the surface of many normal and cancer cells.  By binding to these receptors genefitinib blocks an important pathway that promotes cell division.

Research continues to identify which cancers may be best treated with targeted therapies and to identify additional targets for more types of cancer. 

Note:  We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice. is designed to provide the latest information about chemotherapy to patients and their families, caregivers and friends. For information about the 4th Angel Mentoring Program visit