dimethyl fumarate at a glance
Medicine class
Immunomodulator classed as an other immunosuppressant.
Licensed uses
Relapsing-remitting multiple sclerosis with selected capsules; systemic treatment of adult plaque psoriasis with Skilarence tablets.
What is dimethyl fumarate used for?
Licensed uses represented by the selected products are:
Selected gastro-resistant capsules: relapsing-remitting multiple sclerosis in adults and adolescents aged 13 years and over.
Skilarence gastro-resistant tablets: moderate to severe plaque psoriasis in adults who need systemic treatment.
How does dimethyl fumarate work?
Dimethyl fumarate is rapidly converted to active monomethyl fumarate. Its effects are not fully understood, but it alters inflammatory immune signalling. Relevant pathways include Nrf2 in multiple sclerosis and NF-κB, T-helper-cell balance and inflammatory activity in psoriasis.
dimethyl fumarate preparations and strengths
Capsule
Route: Oral
Strengths: 120 mg, 240 mg
Gastro-resistant capsule
Route: Oral
Strengths: 120 mg
Gastro-resistant tablet
Route: Oral
Strengths: 30 mg, 120 mg
How to take dimethyl fumarate
Follow the instructions for the prescribed product because the capsule and psoriasis-tablet regimens are not interchangeable.
Swallow capsules whole; do not crush, divide, dissolve, suck, chew or open them.
Swallow Skilarence tablets whole with fluid during or immediately after a meal; do not crush, divide, dissolve or chew them.
Food may lessen flushing or stomach and bowel effects.
Avoid large quantities of strong alcoholic drinks around administration because gastrointestinal effects may increase.
dimethyl fumarate side effects
Common or expected effects
- Flushing, warmth, redness, itching or burning
- Diarrhoea, nausea, abdominal pain, indigestion or vomiting
- Reduced lymphocyte or white-cell counts
- Headache, tiredness or reduced appetite
- Itching, rash or skin redness
- Changes in liver enzymes or urine tests
Get urgent medical advice
- New neurological or psychiatric symptoms suggesting PML
- Breathing difficulty, angioedema, faintness or widespread urticaria suggesting anaphylaxis
- Serious infection, including extensive shingles or shingles involving the eye or nervous system
- Jaundice, dark urine or severe unexplained fatigue suggesting liver injury
- Excessive thirst or urination, muscle weakness, unexplained bone pain or stress fractures suggesting renal tubular dysfunction
dimethyl fumarate in pregnancy
Advice differs by product. Multiple-sclerosis capsules are preferably avoided and should be used only after specialist assessment when benefit is considered to justify potential fetal risk. Evidence mainly from early exposure has not shown an increased rate of adverse pregnancy outcomes, but later exposure is less certain. Skilarence is contraindicated during pregnancy.
dimethyl fumarate while breastfeeding
For multiple-sclerosis capsules, an individual decision is required between breastfeeding and treatment. Small studies suggest low transfer of the active metabolite into milk, but infant safety evidence is limited. Skilarence is contraindicated during breastfeeding.
dimethyl fumarate interactions
Check the exact product before combining dimethyl fumarate with other treatments.
Other fumaric acid derivatives
Avoid simultaneous topical or systemic fumarates because safety has not been established and adverse effects may be additive.
Immunosuppressants, antineoplastic treatments and systemic antipsoriatic therapies
Combined immune effects may increase safety risks, requiring specialist review and caution.
Common questions about dimethyl fumarate
Answers are fully visible for fast scanning and source review.
Are the capsules and Skilarence interchangeable?
No. They contain the same active ingredient, but their formulations, licensed indications, contraindications and treatment instructions differ.
Why are blood tests needed?
Dimethyl fumarate can reduce lymphocytes and other white cells, increasing concern about opportunistic infection and PML. Tests also help identify liver or kidney adverse effects.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.