WHY is this medicine prescribed?
Selumetinib is used to treat certain types of neurofibromatosis type 1 (NF1; a nervous system disorder that causes tumors to grow on nerves). Selumetinib is in a class of medications called kinase inhibitors. It works by helping stop tumor growth.
HOW should this medicine be used?
Selumetinib comes as a capsule and granules to take by mouth. Take with or without food twice a day. Take selumetinib at around the same times every day, approximately 12 hours apart.
Take selumetinib exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Swallow the capsules whole with water; do not open, chew, or crush them.
Granules are used when individuals cannot swallow the capsules. Give the granules by sprinkling on or mixing with 1 to 3 teaspoons full of soft food like smooth yogurt or fruit puree made from bananas, apple, pear, or strawberry. Take the mixture within 30 minutes. If not taken within 30 minutes, you must throw it away and make a new mixture. If only part of the combination has been taken in 30 minutes then throw away the remaining amount but do not mix an additional dose. Make sure that for the next dose, the entire combination is taken within 30 minutes.
Do not use the granules if they are clumped or stuck inside the capsules and not free-flowing. Call your pharmacy and throw away the empty shell of the capsule that had contained the granules. Do not swallow or chew these capsule shells. Do not chew or crush the granules ir add them to a liquid. Do not mix the granules in grapefruit juice or mix with any juice, puree, or jam containing Seville oranges.
If you vomit after taking selumetinib, do not take another dose. Continue your regular dosing schedule.
Your doctor may decrease your dose or temporarily or permanently stop your treatment if you experience certain side effects. Be sure to tell your doctor how you are feeling during your treatment with selumetinib.
Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.
Are there OTHER USES for this medication?
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What SPECIAL PRECAUTIONS should I follow?
Before taking selumetinib,
What SPECIAL DIETARY instructions should I follow?
Avoid eating grapefruit or seville orange or drinking grapefruit or seville orange juice while taking this medication.
What should I do IF I FORGET to take a dose?
Take the missed dose as soon as you remember it. However, if it is within 6 hours of the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What SIDE EFFECTS can this medicine cause?
Selumetinib may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:
Selumetinib may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I do in case of OVERDOSE?
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at http://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
What should I know about STORAGE and DISPOSAL of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Do not remove the desiccant (small packet included with the capsules to absorb moisture) from your bottle.
Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reach. http://www.upandaway.org
Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.
What OTHER INFORMATION should I know?
Keep all appointments with your doctor, eye doctor, and the laboratory. Your doctor will order certain lab tests, including eye exams, before, during, and after your treatment to check your body's response to selumetinib.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.
This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.
The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.
AHFS® Patient Medication Information™ Copyright, 2025. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: December 15, 2025.