This site is intended for UK healthcare professionals
Medscape UK Univadis Logo
Medscape UK Univadis Logo


Oral formulations of dimethyl fumarate.

Drugs List

  • dimethyl fumarate 120mg gastro-resistant capsules
  • dimethyl fumarate 240mg gastro-resistant capsules
  • TECFIDERA 120mg gastro-resistant capsules
  • TECFIDERA 240mg gastro-resistant capsules
  • Therapeutic Indications


    Treatment of relapsing-remitting multiple sclerosis



    120mg twice a day.

    After 7 days, the dose is increased to the recommended dose of 240mg twice a day.

    Temporary dose reduction to 120mg twice a day may reduce occurrence of flushing and gastrointestinal adverse reactions. Within 1 month, the recommended dose of 240mg twice a day should be resumed.

    Additional Dosage Information

    Missed doses
    If a dose is missed, a double dose should not be taken. The missed dose may be taken if 4 hours is left between doses, otherwise the patient should wait until the next scheduled dose.


    Absolute lymphocyte count below 0.5 x 10 to the power of 9/L
    Children under 18 years
    Severe infection
    Progressive multifocal leukoencephalopathy (PML)

    Precautions and Warnings

    Antibodies to JC virus
    Females of childbearing potential
    Severe gastrointestinal disorder
    Severe hepatic impairment
    Severe renal impairment

    Administration of live vaccines is not recommended
    Treatment to be initiated and supervised by a specialist
    A recent (within 3 months) MRI should be available prior to treatment
    Monitor renal and hepatic function before and during treatment
    Perform full blood count before treatment
    Evaluate renal function if signs of proximal renal tubulopathy occur
    Monitor full blood counts every 3 months
    Advise patient that flushing reactions may occur
    Advise patient to report headaches, seizures, confusion, visual disturbance
    Advise patient to report symptoms of infection immediately
    Advise patient to seek medical advice if severe flushing occurs
    Consider stopping if lymphocytes below 0.5x10 to power 9/L for 6 months
    Discontinue if anaphylactoid reaction occurs
    Discontinue if Progressive multifocal leukoencephalopathy (PML) develops
    Discontinue treatment if patient develops a serious infection
    Evaluate risk if lymphocyte count below 0.8x10 to power9/L for 6 months
    Advise patient to moderate alcohol intake during treatment
    Female: Ensure adequate contraception during treatment
    Advise patient to report symptoms of herpes zoster urgently

    Prior to initiating treatment with dimethyl fumarate, a recent complete blood count (within 6 months) should be available. Assessments of complete blood counts are also recommended every 3 months and as clinically indicated.

    Assessments of renal function (e.g. creatinine, blood urea nitrogen and urinalysis) are recommended prior to treatment initiation, after 3 and 6 months and then every 6 to 12 months thereafter as clinically indicated.

    If lymphocyte counts are found to be below the normal range prior to treatment, assessments of the possible causes should be completed prior to the initiation of dimethyl fumarate treatment.

    Consider a short course of acetylsalicylic acid in cases of intolerable flushing.

    Severe flushing as a result of dimethyl fumarate treatment may indicate hypersensitivity.

    If symptoms of neurological dysfunction are present, perform an MRI to evaluate patient to determine if these symptoms are typical for multiple sclerosis or suggestive of progressive multifocal leukoencephalopathy syndrome (PML).

    If symptoms suggestive of PML occur, interrupt treatment with dimethyl fumarate and perform appropriate diagnostic evaluations. This includes determination of JCV DNA in cerebrospinal fluid (CSF) by quantitative polymerase chain reaction (PCR) methodology.

    Prolonged moderate to severe lymphopenia appears to increase the risk of PML, patients with mild lymphopenia cannot be excluded either. Prior immunosuppressive or immunomodulatory therapy might also contribute to the risk of PML in the setting of lymphopenia.

    Pregnancy and Lactation


    Dimethyl fumarate is contraindicated during pregnancy.

    The manufacturer does not recommend using dimethyl fumarate during pregnancy. Animal studies have shown teratogenic effects. Human data is limited and as such a potential risk cannot be ruled out.


    Dimethyl fumarate is contraindicated during breastfeeding.

    The manufacturer advises that the patient either discontinues dimethyl fumarate or discontinues breastfeeding. The presence of dimethyl fumarate in human breast milk and the effects on exposed infants are unknown.

    Side Effects

    Abdominal discomfort
    Abdominal distension
    Abdominal pain
    Acute leukaemia
    Alanine aminotransferase increased
    Allergic skin reactions
    Aspartate aminotransferase increased
    Burning sensation
    Decreased appetite
    Fanconi syndrome
    Feeling hot
    Gastrointestinal disorder
    Herpes zoster
    Hot flushes
    Hypersensitivity reactions
    Increases in hepatic enzymes
    Progressive multifocal leukoencephalopathy (PML)
    Renal failure
    Serum creatinine increased
    Upper abdominal pain
    White blood cell count decreased


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: November 2019

    Reference Sources

    Summary of Product Characteristics: Tecfidera 120mg and 240mg gastro-resistant hard capsules. Biogen Idec Ltd. Revised November 2020.

    MHRA Drug Safety Update 30 March 2015
    Available at:
    Last accessed: 8 April 2015.

    MHRA Drug Safety Update 7 January 2021
    Available at:
    Last accessed: 15 January 2021.

    Access the full UK drug database with a FREE Medscape UK Account
    It takes just a few minutes, and you’ll get unlimited access to information on over 11,000 UK drugs.
    Register for Free

    Already a member? Log in

    Medscape UK | Univadis prescription drug monographs & interactions are based on FDB Multilex Content

    FDB Logo

    FDB Disclaimer : FDB Multilex is intended for the use of healthcare professionals and is provided on the basis that the healthcare professionals will retain FULL and SOLE responsibility for deciding what treatment to prescribe or dispense for any particular patient or circumstance.