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Dimethyl fumarate (By mouth)

Dimethyl Fumarate (dye-METH-il FUE-ma-rate)

Treats multiple sclerosis (MS).

Brand Name(s):

Tecfidera, Tecfidera Starter Pack

When This Medicine Should Not Be Used:

How to Use This Medicine:

Delayed Release Capsule

• Your doctor will tell you how much medicine to use. Do not use more than directed.
• Swallow the delayed-release capsule whole. Do not crush or chew it. Do not sprinkle the contents of the capsule on food.
• You may have less skin flushing if you take the medicine with food. Your doctor may give you other medicine (including aspirin) to be taken 30 minutes before taking this medicine to help reduce skin flushing.
• Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Once you have opened a bottle, throw away any unused medicine after 90 days.

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:

• Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding, or if you have stomach or bowel problems, any type of infection (including herpes zoster), or a weak immune system.
• This medicine may cause the following problems:
  • Increased risk of infections, which may be life-threatening, including progressive multifocal leukoencephalopathy (PML) or herpes zoster (shingles)
  • Liver problems
  • Serious stomach or bowel problems (including bleeding, blockage, perforation, or ulcers)
• This medicine lowers the number of white blood cells. This weakens your immune system, so you may get infections more easily. Wash your hands often. Avoid people who are sick.
• 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
• Back pain, blurred vision, dizziness, fever, headache, seizures, tiredness
• Black, tarry stools, constipation, diarrhea, stomach pain or upset, vomiting of blood or material that looks like coffee grounds
• Change in how much or how often you urinate, lower back or side pain, painful or difficult urination
• Chest pain, trouble breathing
• Dark urine or pale stools, nausea, vomiting, loss of appetite, yellow skin or eyes
• Fever or chills, cough, sore throat, body aches
• Painful blisters on trunk of the body
• Warmth or redness in your face, neck, arms, or upper chest

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: 9/6/2024