Mirdametinib (By mouth)

Mirdametinib (mir-da-ME-ti-nib)

Treats neurofibromatosis type 1 (NF1).

Brand Name(s):

Gomekli

When This Medicine Should Not Be Used:

How to Use This Medicine:

Capsule, Liquid

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• Take this medicine about 12 hours apart.
• Swallow the capsule whole. Do not open, break, or chew it.
• You may swallow the tablet for suspension whole with drinking water or disperse the tablet into drinking water.
• Tablet for suspension:
  • Wash and dry your hands before using this medicine.
  • Add about 5 to 10 milliliters (mL) of drinking water to the dosing cup. Add the prescribed number of tablets to the water.
  • Gently swirl the dosing cup to disperse the tablet until no lumps remain. Wait for 2 to 4 minutes until the tablets have fully dispersed. The liquid should be white and cloudy and may contain small pieces.
  • Swallow the mixture right away or within 30 minutes after preparing.
  • If there are small pieces left in the cup, you may add another 5 to 10 mL of drinking water to the dosing cup. Gently swirl the dosing cup and drink the mixture right away.
  • You may also take or give this medicine from an oral dosing syringe. Place the tip of the oral syringe inside the mouth pointing toward inside of either cheek. Slowly push the plunger all the way down to give the full dose. If you are giving this medicine to a child, make sure they are sitting upright until all the liquid has been swallowed.
• 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 you miss a dose, 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.
• Throw away any unused oral liquid 30 minutes after preparing the mixture.

Drugs and Foods to Avoid:

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

Warnings While Using This Medicine:

• This medicine may cause birth defects if either partner is using it during conception or pregnancy. Tell your doctor right away if you or your partner becomes pregnant. If you can get pregnant, your doctor may do tests to make sure you are not pregnant before using this medicine. Use an effective form of birth control to keep from getting pregnant during treatment and for at least 6 weeks after your last dose. Males who are taking this medicine, with female partners who can become pregnant must use effective birth control during treatment and for at least 3 months after the last dose of this medicine.
• Do not breastfeed during treatment 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:
  • Eye or vision problems
  • Heart problems
  • Serious skin reactions, including dermatitis acneiform, eczema
• Some women who use this medicine have become infertile (unable to have children). Talk with your doctor before using this medicine if you plan to have children.
• 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, chills, cough, sore throat, body aches
• Muscle or bone pain
• Severe rash, redness, or acne
• Trouble breathing, fast or uneven heartbeat

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

• Diarrhea, stomach pain, nausea, vomiting
• Headache
• Redness or soreness around the fingernails
• 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: 5/4/2025