Read the Patient Information Leaflet if available from your pharmacist before you start taking osimertinib and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually once daily.

If you have trouble swallowing the tablet whole, place the tablet into a container with a small amount of non-carbonated water (2 ounces/60 milliliters). Stir well until the tablet breaks into small pieces. The tablet will not completely dissolve. Do not crush the tablet or heat the mixture. Drink all of the mixture right away. Add at least another half a glass of water (4 ounces/120 milliliters) to the container and drink all of the mixture to make sure you are getting all of the drug. Use only non-carbonated water for mixing, and do not prepare a supply in advance. The mixture may also be given through a tube into the stomach (nasogastric tube). If you are giving this medication through a nasogastric tube, ask your health care professional for detailed instructions on how to give it.

The dosage is based on your medical condition and response to treatment.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of serious side effects will increase.