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Tecfidera (dimethyl fumarate)

Reviewed by: HU Medical Review Board | Last reviewed: April 2023

Tecfidera® (dimethyl fumarate) is a drug approved to treat relapsing forms of multiple sclerosis (MS) in adults, including:1

  • Clinically isolated syndrome (CIS)
  • Relapsing-remitting MS (RRMS)
  • Active secondary progressive MS (SPMS)

Tecfidera is a disease-modifying drug (DMD) that may delay the buildup of disability.1

What are the ingredients in Tecfidera?

The active ingredient in Tecfidera is dimethyl fumarate.1

How does Tecfidera work?

The way Tecfidera works is not well understood. It is thought to act by reducing inflammation and the immune response that attacks the sheath (myelin) that forms around nerves, including in the brain and spinal cord. It may also protect nerve cells from damage caused by chemicals released during an immune attack.1

What are the possible side effects of Tecfidera?

Many clinical trials evaluated the safety and efficacy of Tecfidera. The most common side effects of Tecfidera include:1

  • Red or hot skin, itching, rash
  • Stomach pain
  • Diarrhea
  • Nausea, vomiting, upset stomach

Tecfidera may also cause serious side effects, including:1

  • Allergic reaction, such as welts, hives, breathing problems, and swelling of the face, lips, mouth, or tongue
  • Decreases in white blood cell counts
  • Liver problems
  • Infections, including shingles and central nervous system infections
  • Liver problems
  • PML, a rare brain infection that can lead to death or severe disability

Contact your doctor right away if you have any symptoms of serious side effects.1

These are not all the possible side effects of Tecfidera. Talk to your doctor about what to expect when taking Tecfidera. You also should call your doctor if you have any changes that concern you when taking Tecfidera.

Other things to know about Tecfidera

Before starting Tecfidera, tell your doctor if you:

  • Are allergic to dimethyl fumarate
  • Have or have had low white blood cell counts or an infection
  • Any other medical conditions

Your doctor will do blood tests to check your liver function and white blood cell count before and during treatment with Tecfidera. Tell your doctor right away if you have signs of liver problems while taking Tecfidera:1

  • Severe tiredness
  • Loss of appetite
  • Pain on the right side of your stomach
  • Have dark or brown urine
  • Yellowing of your skin or the white part of your eyes

There is not enough data to know if Tecfidera is safe to take while pregnant or breastfeeding. Tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding before starting Tecfidera.1

Before beginning treatment for MS, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.

For more information, read the full prescribing information of Tecfidera.

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