diroximel fumarate at a glance
Medicine class
Fumarate immunomodulator and disease-modifying treatment
Licensed use
Relapsing-remitting multiple sclerosis in adults
Form
Gastro-resistant hard capsules for oral use
Food
May be taken with or without food; food may ease flushing or stomach symptoms
What is diroximel fumarate used for?
It is licensed for:
Treatment of relapsing-remitting multiple sclerosis in adults.
How does diroximel fumarate work?
Diroximel fumarate is rapidly converted to the active metabolite monomethyl fumarate. Its full mechanism is uncertain, but it partly activates the Nrf2 antioxidant pathway and modifies inflammatory immune-cell activity involved in MS.
diroximel fumarate preparations and strengths
Capsule
Route: Oral
Strengths: 231 mg
How to take diroximel fumarate
Follow the specialist's prescription and supplied leaflet.
Swallow capsules whole and intact with water.
Do not crush, chew, open or sprinkle their contents onto food.
They may be taken with or without food. Food may improve flushing or gastrointestinal symptoms.
diroximel fumarate side effects
Common or expected effects
- Flushing, warmth, redness, itching or burning
- Diarrhoea, nausea, abdominal pain or cramps
- Vomiting, indigestion or gastritis
- Rash or itching
- Reduced lymphocyte or white-cell counts
- Raised liver enzymes or protein in the urine
- Hair loss
Get urgent medical advice
- Severe allergic reaction
- New neurological symptoms suggesting progressive multifocal leukoencephalopathy
- Serious infection, including severe or widespread shingles
- Possible liver injury, including jaundice or dark urine with marked illness
- Possible Fanconi syndrome, including excessive thirst or urination, muscle weakness, unexplained bone pain or fractures
diroximel fumarate in pregnancy
Human pregnancy data are limited. Diroximel fumarate is not recommended during pregnancy unless a specialist considers it clearly necessary after weighing benefits and fetal risks. Appropriate contraception is advised where pregnancy is possible. Discuss pregnancy plans or an unplanned pregnancy promptly with the MS team rather than changing treatment without advice.
diroximel fumarate while breastfeeding
It is unknown whether diroximel fumarate or its metabolites enter human milk, and risk to a breastfed child cannot be excluded. The MS and maternity teams should weigh the benefits of breastfeeding against the benefits of treatment.
diroximel fumarate interactions
Tell the specialist or pharmacist about all prescribed, non-prescribed and complementary products.
Dimethyl fumarate
Do not use concurrently because both produce the same active metabolite and may compound adverse effects.
Other fumaric acid esters
Avoid concurrent topical or systemic fumarates because combined exposure may increase toxicity.
Anticancer or immunosuppressive therapies
Combined use has not been adequately studied and may cause additive immune effects or infection risk.
Common questions about diroximel fumarate
Answers are fully visible for fast scanning and source review.
Is diroximel fumarate the same as dimethyl fumarate?
No. They are different fumarates, but both are converted to monomethyl fumarate. They should not be taken together or exchanged without specialist direction.
Does diroximel fumarate cure multiple sclerosis?
No. It is intended to reduce inflammatory MS activity rather than cure the condition.
Why are blood tests needed?
It can lower lymphocytes and other white cells and may affect liver or kidney test results. Monitoring helps identify important changes and PML risk.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.