Dimethyl Fumarate

About Dimethyl Fumarate

Dimethyl fumarate is converted in the body to monomethyl fumarate; exactly how it helps in multiple sclerosis is not known. It is labeled for relapsing forms of MS in adults, which include clinically isolated syndrome, relapsing-remitting disease and active secondary progressive disease. It starts at 120 mg twice a day for seven days and then continues at 240 mg twice a day. If the full dose is not tolerated, the prescriber may lower it to 120 mg twice a day for up to four weeks before returning to 240 mg; someone who still cannot tolerate it may need to stop.

Flushing (warmth, redness, itching or burning of the skin), stomach pain, diarrhea and nausea are the most common side effects; taking it with food may reduce flushing. The label warns of anaphylaxis and angioedema, which can follow the first dose or come at any time during treatment; of progressive multifocal leukoencephalopathy (PML), a rare brain infection that has occurred in people with low lymphocyte counts; of shingles and other serious infections; of liver injury; and of serious stomach and bowel reactions, including perforation, ulcers, bleeding and blockage. A complete blood count with lymphocytes is taken before starting, after six months and every six to twelve months after that, and liver tests before starting and as needed; treatment may be interrupted if lymphocytes stay very low for more than six months, or withheld during a serious infection. It must not be taken by anyone allergic to it.

The capsules are delayed-release and are swallowed whole, never crushed, chewed or sprinkled on food. Vumerity (diroximel fumarate) and Bafiertam (monomethyl fumarate) are related medicines that act through the same compound; they are different products, not substitutes for dimethyl fumarate at the counter, and their labels rule out taking them with it. Pregnancy registry and other data have not shown a higher risk of major birth defects or miscarriage, but pregnancy plans are still discussed with the prescriber.

Taking Dimethyl Fumarate

How to take it

Twice a day, with or without food; taking it with food may reduce flushing. Swallow each capsule whole; do not crush, chew or open it or sprinkle the contents on food. The label also notes that non-enteric-coated aspirin, up to 325 mg, taken 30 minutes before a dose may reduce flushing, which is for the prescriber to recommend.

If you miss a dose

Take it as soon as you remember, unless it is almost time for the next dose; then skip the missed dose. Do not take two doses at once.

Storage

At room temperature in the original container, protected from light, heat and moisture.

Interactions to know about

Do not take it with Vumerity or Bafiertam, whose labels rule out combining them with dimethyl fumarate. Live vaccines given during treatment have not been studied. Tell the prescriber about a low white blood cell count or any infection, and report swelling of the face or tongue, trouble breathing, or new weakness on one side of the body, clumsiness, vision changes or confusion at once.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Dimethyl Fumarate differs from pharmacy to pharmacy

Generic dimethyl fumarate has many makers, all rated equivalent to Tecfidera, yet pharmacies price it in very different ways: some start from what they paid plus a fee, others from a published list price. That is why quotes for the same capsule can differ widely, and a prescription that names Tecfidera without allowing substitution is quoted at the brand price.

Treatment starts with a week of 120 mg capsules and continues on 240 mg capsules; the brand and some generics also come as a 30-day starter pack holding both strengths. The first fill and later fills are therefore priced differently, and a pharmacy that rarely dispenses it may need to order either strength.

Ways to pay less for Dimethyl Fumarate without insurance

• Make sure the prescription allows generic substitution, so you are quoted for generic dimethyl fumarate rather than Tecfidera.
• Compare more than one pharmacy for the same strength and quantity.
• Once you are on the maintenance dose, ask for a ninety-day supply of the 240 mg capsules.
• If you need the brand, ask its maker whether a patient assistance program applies to someone paying cash.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Dimethyl Fumarate

1. 1.Is this the generic, and is it the 120 mg starting capsule or the 240 mg capsule?
2. 2.How can I reduce flushing and stomach upset?
3. 3.When are my blood count and liver tests due?
4. 4.Which signs of infection, liver trouble or allergic reaction mean I should call at once?

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