Gefitinib

Gefitinib

Generic name: gefitinib [ ge-FI-ti-nib ]
Brand name: Iressa
Dosage form: Oral tablet (250 mg)
Drug class: EGFR inhibitors

What is Gefitinib?

Gefitinib is a targeted cancer therapy that helps block the growth and spread of cancer cells in the body. It belongs to a group of medicines known as EGFR (epidermal growth factor receptor) inhibitors.

It is primarily used for the treatment of non-small cell lung cancer (NSCLC), especially in patients whose cancer has specific EGFR mutations. In some cases, it may also be used when the cancer has spread to other parts of the body.

Gefitinib Side Effects

Seek immediate medical help if you experience signs of an allergic reaction:

• Hives
• Difficulty breathing
• Swelling of the face, lips, tongue, or throat

Serious side effects may include:

• Severe or persistent diarrhoea
• New or worsening cough, chest pain, breathing difficulty
• Eye problems (pain, blurred vision, redness, light sensitivity)
• Liver issues (yellowing of the skin or eyes, dark urine, loss of appetite)
• Severe skin reactions (blistering, peeling, painful rash)

Common side effects may include:

• Diarrhoea
• Skin rash or acne
• Itching or dry skin

Warnings

• Do not take Gefitinib if you are allergic to gefitinib.
• Gefitinib can cause serious side effects, including liver damage, lung complications, or severe skin reactions.
• Do not take this medicine if you are pregnant, as it may harm the unborn baby. Use effective contraception while taking this medicine and for at least 2 weeks after the last dose.
• Avoid using stomach acid reducers like omeprazole or ranitidine within 6 hours of taking gefitinib.
• Always inform your doctor of all other medicines you are taking, including over-the-counter and herbal products.

Before Taking

Let your doctor know if you have or have had:

• Liver or kidney disease
• Breathing problems or lung conditions (other than lung cancer)
• Vision problems
• If you take blood thinners (e.g., warfarin)

Women should inform their doctor if they are pregnant or breastfeeding. It is not known if gefitinib passes into breast milk, so breastfeeding is not recommended during treatment.

What to Avoid?

• Do not take antacids or acid-reducing medicines like omeprazole, lansoprazole, or ranitidine within 6 hours before or after taking gefitinib, as they may reduce its effectiveness.
• Avoid becoming pregnant while taking this medicine and for 2 weeks after stopping treatment.
• Do not breastfeed while on gefitinib.
• Avoid sharing this medicine with others, even if they have similar symptoms.

Interactions

Tell your doctor about all medicines you’re taking. Some drugs may reduce the effectiveness of gefitinib or increase side effects. Be especially cautious if taking:

• Warfarin or other blood thinners
• Antacids or PPIs (like omeprazole or lansoprazole)
• Herbal supplements

Always consult your pharmacist or doctor before starting or stopping any medicine.

How Should I Take Gefitinib?

• Take exactly as prescribed by your doctor—usually 250 mg once daily, with or without food.
• Swallow the tablet whole with water. If you can’t swallow tablets, you can:
  • Dissolve the tablet in 4 to 8 ounces of plain water (not fizzy), stir for 15 minutes and drink immediately.
  • Rinse the glass with another 4 to 8 ounces of water and drink to ensure the full dose is taken.
  • This liquid can also be given via a nasogastric (NG) tube.
• Regular blood tests may be needed to check your liver function during treatment.
• Store the tablets at room temperature, away from heat and moisture.

Dosage

Usual adult dose for NSCLC:

• 250 mg by mouth once daily, continued until disease progression or unacceptable side effects occur.

Important: Patients must be selected based on the presence of EGFR mutations in their tumor (exon 19 deletions or exon 21 L858R substitutions), as identified by an approved test.

What Happens If I Miss a Dose?

• If you miss a dose, take it as soon as you remember.
• If your next dose is due in less than 12 hours, skip the missed dose—do not double up.

What Happens If I Overdose?

• Seek emergency medical help immediately.
• Signs of overdose may include severe diarrhoea, nausea, vomiting, and rash.

Frequently Asked Questions (FAQ)

Can I take gefitinib with food?
Yes, it can be taken with or without food.

Is gefitinib safe during pregnancy?
No, it can harm an unborn baby. Use effective contraception during treatment and for 2 weeks after stopping.

Can I crush the tablet?
If you can’t swallow it whole, dissolve it in plain water as instructed.

Does it affect fertility?
It may reduce fertility in women. Talk to your doctor if you plan to have children in the future.

Always follow your doctor’s guidance and do not make changes to your medication without consulting a healthcare professional.