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Monomethyl Fumarate

Why is this medication prescribed?

Monomethyl fumarate is used to treat adults with various forms of multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control) including:

  • clinically isolated syndrome (CIS; nerve symptom episodes that last at least 24 hours),
  • relapsing-remitting forms (course of disease where symptoms flare up from time to time), or
  • secondary progressive forms (course of disease where relapses occur more often).

Monomethyl fumarate is in a class of medications called Nrf2 activators. It works by decreasing inflammation and preventing nerve damage that may cause symptoms of multiple sclerosis.

How should this medicine be used?

Monomethyl fumarate comes as a delayed-release (releases the medication in the intestine to prevent break-down of the medication by stomach acids) capsule to take by mouth. It is usually taken twice a day. Take monomethyl fumarate at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take monomethyl fumarate exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Monomethyl fumarate may be taken with or without food.

Swallow the capsules whole; do not chew or crush them. Do not open the capsules or sprinkle the contents on food.

You may take a non-enteric coated aspirin (325 mg or less) 30 minutes before taking monomethyl fumarate to reduce the chance of flushing (facial redness) during your treatment.

Your doctor will probably start you on a low dose of monomethyl fumarate and increase your dose after 7 days.

Monomethyl fumarate may help to control multiple sclerosis, but will not cure it. Continue to take monomethyl fumarate even if you feel well. Do not stop taking monomethyl fumarate without talking to your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking monomethyl fumarate,

  • tell your doctor and pharmacist if you are allergic to monomethyl fumarate, dimethyl fumarate (Tecfidera), diroximel fumarate (Vumerity) any other medications, or any of the ingredients in monomethyl fumarate capsules. Ask your pharmacist or check the manufacturer's patient information for a list of the ingredients.
  • tell your doctor if you are taking dimethyl fumarate (Tecfidera) or diroximel fumarate (Vumerity). Your doctor will probably tell you not to take monomethyl fumarate if you are taking one of these medications.
  • tell your doctor if you have any type of infection, including infections that come and go and chronic infections that do not go away, or if you have or have ever had chickenpox or herpes zoster (shingles; a rash that can occur in people who have had chickenpox in the past); or if you have a low white blood cell count or liver or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking monomethyl fumarate, call your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for 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 medication cause?

Monomethyl fumarate may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • warmth, redness, itching, or burning of the skin
  • diarrhea
  • nausea
  • vomiting
  • heartburn
  • stomach pain
  • hair loss
  • runny nose

Some side effects can be serious. If you experience any of these symptoms, stop taking monomethyl fumarate and call your doctor immediately or get emergency medical treatment:

  • difficulty swallowing or breathing
  • swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
  • hives, rash, itching
  • hoarseness
  • weakness on one side of the body that worsens over time, clumsiness in your arms or legs, vision problems, changes in thinking and memory, confusion, or personality changes
  • extreme tiredness, loss of appetite, pain in upper right side of your stomach, dark urine, or yellowing of the skin or eyes
  • cough; sore throat; fever; warm, red, or painful skin; or other signs of infection
  • ongoing pain that begins in the stomach area but may spread to the back, nausea, vomiting, or loss of appetite

Monomethyl fumarate may cause other side effects. Call your doctor if you have any unusual problems while you are 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 ( or by phone (1-800-332-1088).

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 light, excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order a blood test before you begin your treatment and may order certain lab tests during your treatment to check your body's response to monomethyl fumarate.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Bafiertam®

Other names

  • MMF
Last Revised - 03/15/2023