Gefitinib
Indications
Gefitinib is a targeted cancer medicine used to treat adults with advanced or spreading non small cell lung cancer (NSCLC) whose tumour has certain changes (activating mutations) in a gene called EGFR. A test on the tumour or blood is done first to confirm these changes.
How It Works
EGFR is a protein on the surface of some cancer cells that sends signals telling them to grow and divide. When EGFR is changed by a mutation, it is switched on all the time. Gefitinib blocks this protein (it is a tyrosine kinase inhibitor), which slows or stops the growth of these cancer cells and can shrink the tumour.
Dosage and Administration
Take Gefitinib exactly as prescribed by your cancer specialist, usually once a day at about the same time, with or without food. Swallow the tablet whole with water. If you cannot swallow it, it can be dispersed in half a glass of plain water as your doctor or pharmacist explains. Do not change or stop the dose without advice. Regular blood tests and scans are needed.
Interactions
Medicines that reduce stomach acid, such as Omeprazole, Esomeprazole or Ranitidine, can lower Gefitinib levels; ask your doctor how to time them. Rifampicin, Carbamazepine, Phenytoin and St John's Wort reduce its effect, while Ketoconazole, Itraconazole and Clarithromycin may increase side effects. It can raise the effect of Warfarin, so blood clotting tests are needed. Avoid grapefruit juice.
Contraindications
- Allergy to Gefitinib or any ingredient of the tablet.
- Breastfeeding.
Side Effects
Very common effects are diarrhoea, an acne like rash, dry or itchy skin, nail problems, loss of appetite, nausea, mouth sores and raised liver enzymes in blood tests. Some people get red, dry or irritated eyes, or hair thinning.
Get urgent medical help if you have new or worsening shortness of breath, cough or fever (which can be a sign of serious lung inflammation), severe or ongoing diarrhoea, yellowing of the skin or eyes, severe blistering or peeling skin, or sudden eye pain or loss of vision.
Pregnancy and Lactation
Gefitinib may harm an unborn baby. Women who could become pregnant should use reliable contraception during treatment and for at least one month after the last dose. Breastfeeding must be stopped during treatment.
Precautions and Warnings
Your doctor will check liver function regularly. Tell your doctor if you have lung problems, liver disease, eye problems or a history of stomach ulcers or bowel perforation. Wear contact lenses only if your doctor agrees. Protect your skin from strong sun. If you feel weak or tired, take care with driving. Handle tablets carefully and keep them away from other people, especially pregnant women and children.
Overdose
There is no specific antidote. Overdose may cause more diarrhoea and skin rash. Contact your doctor or hospital immediately.
Therapeutic Class
Antineoplastic (anticancer) agent; EGFR tyrosine kinase inhibitor.
Storage
Store below 30°C in a dry place, away from light and out of the reach of children. Keep in the original package.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.
All brands of Gefitinib