Selumetinib (By mouth)

Selumetinib (sel-ue-ME-ti-nib)

Treats neurofibromatosis type 1 (NF1).

Brand Name(s):

Koselugo

When This Medicine Should Not Be Used:

How to Use This Medicine:

Capsule

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• Take this medicine at least 1 hour before or 2 hours after a meal. Allow at least 12 hours between each dose.
• Swallow the capsule whole with water. Do not chew, dissolve, or open it.
• Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
• Missed dose: If it is more than 6 hours until the time you normally take a dose, take it as soon as you remember. If it is less than 6 hours until your regular time, skip the missed dose and go back to your regular dosing schedule. If you vomit after taking your medicine, do not take an extra dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Some medicines can affect how selumetinib works. Tell your doctor if you are using fluconazole, St John's wort, blood thinners, vitamin E supplements, or vitamin K antagonists.
• Do not eat grapefruit or drink grapefruit juice while you are using this medicine.

Warnings While Using This Medicine:

• It is not safe to take this medicine during pregnancy. It could harm an unborn baby. Tell your doctor right away if you become pregnant. Use an effective form of birth control during treatment with this medicine and for 1 week after the last dose. Male patients with female partners should use an effective form of birth control during treatment and for 1 week after the last dose.
• Do not breastfeed during treatment with this medicine and for at least 1 week after the last dose.
• Tell your doctor if you have kidney disease, liver disease, heart disease, or eye or vision problems.
• This medicine may cause the following problems:
  • Heart problems
  • Eye or vision problems
  • Stomach or bowel problems
  • Serious skin reactions
  • Muscle problems (including myopathy, rhabdomyolysis)
  • Increased risk of bleeding problems
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Blurred vision or changes in vision
• Fever, dark urine
• Muscle pain, tenderness, or weakness
• Rapid weight gain, swelling in your hands, ankles, or feet
• Severe diarrhea
• Severe rash, redness, or acne
• Trouble breathing, fast or uneven heartbeat
• Unusual bleeding, bruising, or weakness

If you notice these less serious side effects, talk with your doctor:

• Constipation, nausea, vomiting, stomach pain
• Headache
• Loss of appetite
• Sores or white patches on your lips, mouth, or throat
• Tiredness

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 12/4/2023