Gefitinib is used to treat lung cancer that has spread to other parts of the body.
Take Gefitinib exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
You may take this medicine with or without food. Try to take it at the same time each day.
Swallow the tablet whole with a glass of water. Do not divide, chew or crush the tablet.
If you have difficulty swallowing tablet(s), you may dissolve the whole tablet in half a glass of water. Do not use any other type of drink. Do not use carbonated water. Drop the tablet in the plain water and stir it for about 10 minutes until the tablet dissolves. Do not crush the tablet. Once the tablet has dissolved, drink the solution immediately. Rinse the glass with another half a glass of plain water and drink. This is to make sure that no medicine is left behind in the glass.
Gefitinib must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.
If you miss a dose and it is 12 hours or more before the next dose is due, take the missed dose and return to your normal dosing schedule.
If it is less than 12 hours before the next dose is due, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, inform your doctor and pharmacist.
Do not breastfeed while you are being treated with Gefitinib.
Inform your doctor if you have the following conditions:
- lung problems
- history of eye problems
- low stomach acidity e.g. achlorhydria (absence or low production of acid in the stomach)
- conditions which increase the risk of developing stomach problems e.g. history of ulcer, smoking
- moderate to severe liver disease
- kidney disease
It is important that you do not get pregnant while being treated with this medicine. You must use proven birth control methods during Gefitinib therapy and for at least 2 weeks after stopping the treatment. You may wish to discuss birth control methods with your doctor or pharmacist.
Some genetic traits can affect this medicine’s efficacy. Individuals who have reduced CYP2D6 enzyme activity, known as CYP2D6 poor metabolisers, may experience an increased Gefitinib exposure and risk of enhanced side effects. If you know you have this gene type, inform your doctor.
Keep your appointments with your doctor. For as long as you are taking this medicine, your doctor may need to perform blood tests to make sure that your liver/kidney function is normal before you take this medicine and thereafter depending on your doctor’s advice.
Gefitinib may cause unusual weakness. If affected do not drive or take part in any activity in which you need to be alert.
Avoid exposure to direct sunlight as it may worsen any skin reactions that may occur. Use a moisturiser regularly, wear protective clothing and apply sunscreen when going outdoors.
Other side effects may include any of the following: diarrhoea, vomiting, nausea, loss of appetite, redness or soreness of mouth, dry mouth, nose bleeding, burning sensation during urination, nail problems, hair loss, and itchy, dry, red or cracked skin.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- difficulty of breathing
- pain in the eye with redness, tearing and blurred vision
- yellowing of the skin or eyes
- fever with persistent sore throat or mouth ulcers, unusual bleeding or bruising
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- medicines for epilepsy (fits or seizures) e.g. phenytoin, phenobarbital, carbamazepine
- medicines to treat fungal infections e.g. ketoconazole, itraconazole, voriconazole, posaconazole
- medicines for HIV infection e.g. ritonavir, saquinavir, indinavir
- certain antibiotics e.g. clarithromycin, telithromycin
- stomach medicines e.g. ranitidine, omeprazole, pantoprazole
- rifampicin (medicine to treat tuberculosis or TB)
- metoprolol (medicine for high blood pressure)
- warfarin (blood-thinning medicine)
- St. John's wort (herbal medicine)
This list does not include all medicines that may interact with Gefitinib.
Gefitinib should not be taken with antacids as it could reduce the effectiveness of this medicine. If you must take antacids, take it at least 6 hours before or after you have taken this medicine.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
Avoid excessive consumption of grapefruit or grapefruit juice.
Store in a cool, dry place away from the reach of children. Protect from moisture.
Medicines must not be used past the expiry date.
As this is a cancer medicine, always return any unused or expired tablets to the clinic, hospital or pharmacy for disposal. Do not throw it away in the household waste.