Dimethyl Fumarate (Tecfidera) is an oral medication used to treat relapsing forms of multiple sclerosis (MS). It is indicated for adult patients with clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease.
Precautions for Dimethyl Fumarate (Tecfidera) Administration
Patient Selection and Contraindications
Contraindications: It is contraindicated in patients with a known allergy to dimethyl fumarate or any component of Tecfidera. Allergic reactions may include immediate hypersensitivity reactions and angioedema.
Baseline tests:
Complete blood count: Including lymphocyte count, which must be tested before treatment and rechecked every 6–12 months after treatment initiation.
Liver function: Test the levels of serum transaminases, alkaline phosphatase, and total bilirubin.
Administration in Special Populations
Pregnant women: Animal studies have shown that dimethyl fumarate may be harmful to the fetus. Women of childbearing age must use effective contraceptive measures (non-hormonal contraceptives are more reliable) during treatment and for 3 months after discontinuing the medication.
Lactating women: Avoid breastfeeding during treatment and for 2 months after the last dose.
Children and elderly patients: The safety of dimethyl fumarate in children under 18 years of age has not been established. Elderly patients require individualized assessment.
Drug Interactions
Aspirin: It can alleviate flushing symptoms. It is recommended to take aspirin (non-enteric-coated tablets, dose ≤ 325mg) 30 minutes before taking dimethyl fumarate.
CYP1A2 inhibitors/inducers: Concomitant use of potent CYP1A2 inhibitors (e.g., fluvoxamine) or moderate inducers (e.g., phenytoin) should be avoided, as they may affect drug concentrations.
Hormonal contraceptives: Dimethyl fumarate may reduce their effectiveness. It is recommended to switch to non-hormonal contraceptive methods.
Monitoring During Dimethyl Fumarate (Tecfidera) Administration
Lymphocyte Count Monitoring
Monitoring frequency: Before treatment, 6 months after treatment initiation, and then every 6–12 months thereafter.
Clinical management: If the lymphocyte count is < 0.5×10⁹/L for more than 6 consecutive months, consider interrupting treatment.
Suspend medication during severe infections until the infection is resolved.
Liver Function Monitoring
Monitoring indicators: ALT, AST, alkaline phosphatase, and total bilirubin.
Management of abnormalities: If transaminases are > 5 times the upper limit of normal (ULN) or bilirubin is > 2 times ULN, discontinue the medication immediately.
Emergency evaluation is required if symptoms such as jaundice, abdominal pain, or fatigue occur.
Infection Risk Monitoring
Herpes viruses: Be alert to herpes zoster (including disseminated herpes, herpetic meningitis, etc.). Suspend medication during the infection period.
Other opportunistic infections: Such as Listeria monocytogenes and Mycobacterium tuberculosis. Timely diagnosis and treatment are required when infection symptoms appear.

