Frequently asked questions

Get the answers you need about treating relapsing MS with Tecfidera® (dimethyl fumarate).

What should I do before I start taking TECFIDERA?

To get started with TECFIDERA, you need one blood draw and you can begin treatment. You can expect your healthcare provider to check your white blood cell count before you take TECFIDERA and occasionally during treatment. Your healthcare provider should also run blood tests to check your liver function before starting TECFIDERA and as necessary during treatment.

How should I take TECFIDERA?

When taking TECFIDERA, it's important to keep the following in mind:

  • Take TECFIDERA exactly as your healthcare provider tells you to take it
  • The recommended starting dose is one 120-mg pill taken by mouth 2 times a day for 7 days
  • The recommended dose after 7 days is one 240-mg pill taken by mouth 2 times a day
  • TECFIDERA can be taken with or without food
  • Swallow TECFIDERA whole. Do not crush, chew, or sprinkle pill contents on food
  • Protect TECFIDERA from light. You can do this by storing the pills in their original container
  • If you take too much TECFIDERA, call your healthcare provider or go to the nearest hospital emergency room right away

Read more about TECFIDERA dosing.

Can I miss a dose of TECFIDERA?

Taking TECFIDERA exactly as prescribed by your healthcare provider gives you the best chance of getting its full benefits. Recommended dosing for TECFIDERA is one pill taken twice a day. If you have questions or concerns, your healthcare provider is your best source of information.

Can I take TECFIDERA if I'm pregnant?

There isn't enough data on the development risk associated with the use of TECFIDERA in pregnant women, including whether exposure is harmful to the mother or to the development of the fetus. Be sure to speak to your healthcare provider as soon as you learn that you are pregnant or if you're planning to become pregnant.

The TECFIDERA Pregnancy Registry study is now closed. If you become pregnant while taking TECFIDERA, talk to your healthcare provider.

How does TECFIDERA work?

During times of inflammation, the body produces toxins that can cause oxidative stress. When this oxidative stress builds up, it can damage cells or even destroy them in different parts of the body, including the central nervous system (CNS). Inflammation within your CNS can also cause oxidative stress, and oxidative stress may trigger more inflammation.

One way the body combats inflammation is through the Nrf2 pathway. This pathway is a complex communication system that defends cells against oxidative stress.

Although we don’t know exactly how TECFIDERA works against relapsing MS, researchers have learned that TECFIDERA leads to activation of the Nrf2 pathway. This may help defend against oxidative stress. Talk with your doctor to learn more about your treatment options.

Does TECFIDERA have serious side effects?

Some serious side effects of TECFIDERA include:

  • allergic reactions
  • PML (a rare brain infection that usually leads to death or severe disability)
  • decreases in your white blood cell count
  • liver problems
  • herpes zoster infections (shingles), including central nervous system infections
  • other serious infections
  • severe gastrointestinal problems

What are the most common side effects of TECFIDERA?

Flushing and stomach problems are the most common side effects of TECFIDERA. Flushing symptoms are usually described as redness, itching, or rash. Stomach symptoms include nausea, vomiting, diarrhea, stomach pain, or indigestion. 

Learn more about the most common side effects of TECFIDERA and how they tended to decrease over time in clinical trials.

What should I do if I experience common side effects?

If you're experiencing any of the common side effects of TECFIDERA, talk to your healthcare provider about trying the tips below: 

  • Tips for flushing

Taking a non-coated aspirin (up to 325 mg) half an hour before taking TECFIDERA may help with flushing. Another tip that may help is taking TECFIDERA after a meal.

  • Tips for stomach problems

Taking TECFIDERA with food may help with stomach problems.* High-fat foods like peanut butter, cheese, or yogurt may be particularly helpful. If you decide to take TECFIDERA with food, it should be taken after you eat. Visit the USDA website for more about how fats fit into a healthy diet.

You can also ask your healthcare provider or pharmacist about over-the-counter medicines, like antacids, since that may help.* Read more about tips for handling the most common side effects.


*In a small 12-week study, people recorded their experience of managing stomach problems while on TECFIDERA. They found that taking it with food or over-the-counter medications could help.

How long do common side effects last?

In clinical trials, common side effects tended to happen earlier in treatment and usually decreased over time. Keep in mind that everyone is different and may react differently to the same medication.

What’s PML?

PML is a rare brain infection that usually leads to death or severe disability over a period of weeks or months. Tell your healthcare provider right away if you get any of these symptoms of PML:

  • weakness on one side of the body that gets worse
  • clumsiness in your arms or legs
  • vision problems
  • changes in thinking and memory
  • confusion
  • personality changes

How effective is TECFIDERA?

How can I tell if TECFIDERA is working?

Talking to your healthcare provider about the results of your MRI could help with the management of your relapsing multiple sclerosis (MS). Lesions revealed on an MRI scan may help your healthcare provider determine how well your treatment is working.

What kind of support does TECFIDERA offer?

If you’re living with relapsing multiple sclerosis (MS), know that you’re not alone. If your healthcare provider prescribes you brand-name TECFIDERA, you will also receive Biogen Support Services. These services can provide help with:

  • Financial assistance
  • Navigating insurance
  • Learning more about your therapy

Remember, your healthcare team is always your best source of information.

What can I do if my insurance doesn't cover TECFIDERA?

At Biogen, our goal is for everyone to get the support they need so they can afford their brand-name TECFIDERA. Biogen Support Coordinators can work with you to understand your insurance coverage and medication cost, and explore financial assistance options for your treatment. Call 1-800-456-2255 to learn more about what financial support resources are available for brand-name TECFIDERA with Biogen Support Services.

How can I find out if I’m eligible for the Biogen Copay Program*?

Biogen Support Coordinators can help identify potential options for financial assistance with your brand-name TECFIDERA if you are:

  • Commercially insured
  • Government insured
  • Uninsured or underinsured

Call Biogen Support Services at 1-800-456-2255 to see if you’re eligible.

*There is an annual cap on the amount of assistance that patients can receive over a one-year period. Federal and state laws and other factors may prevent or otherwise restrict eligibility. People covered by Medicare, Medicaid, the VA/DoD, or any other federal plans are not eligible to enroll. You are eligible to enroll in the Biogen Copay Program for as long as it is offered and you are treated with a Biogen relapsing MS medication. The Biogen Copay Program is no longer available for TECFIDERA patients in the states of Massachusetts and California.

How can a Nurse Educator help me?

Nurse Educators are registered nurses, working on behalf of Biogen, and many are MS-certified. Nurse Educators can:

  • Answer questions or provide information related to your relapsing MS and brand-name TECFIDERA
  • Provide ongoing phone support on how to take your medication and help manage common side effects
  • Review instructions from your healthcare provider and connect you with available resources

Biogen Support Services offers free access to Nurse Educators Monday-Friday from 8:30 AM to 8 PM ET. To reach one, call 1-800-456-2255. Support is also available in Spanish.

Explore topics:

TAKING TECFIDERA

What should I do before I start taking TECFIDERA?

To get started with TECFIDERA, you need one blood draw and you can begin treatment. You can expect your healthcare provider to check your white blood cell count before you take TECFIDERA and occasionally during treatment. Your healthcare provider should also run blood tests to check your liver function before starting TECFIDERA and as necessary during treatment.

How should I take TECFIDERA?

When taking TECFIDERA, it's important to keep the following in mind:

  • Take TECFIDERA exactly as your healthcare provider tells you to take it
  • The recommended starting dose is one 120-mg pill taken by mouth 2 times a day for 7 days
  • The recommended dose after 7 days is one 240-mg pill taken by mouth 2 times a day
  • TECFIDERA can be taken with or without food
  • Swallow TECFIDERA whole. Do not crush, chew, or sprinkle pill contents on food
  • Protect TECFIDERA from light. You can do this by storing the pills in their original container
  • If you take too much TECFIDERA, call your healthcare provider or go to the nearest hospital emergency room right away

Read more about TECFIDERA dosing.

Can I miss a dose of TECFIDERA?

Taking TECFIDERA exactly as prescribed by your healthcare provider gives you the best chance of getting its full benefits. Recommended dosing for TECFIDERA is one pill taken twice a day. If you have questions or concerns, your healthcare provider is your best source of information.

Can I take TECFIDERA if I'm pregnant?

There isn't enough data on the development risk associated with the use of TECFIDERA in pregnant women, including whether exposure is harmful to the mother or to the development of the fetus. Be sure to speak to your healthcare provider as soon as you learn that you are pregnant or if you're planning to become pregnant.

The TECFIDERA Pregnancy Registry study is now closed. If you become pregnant while taking TECFIDERA, talk to your healthcare provider.

How does TECFIDERA work?

During times of inflammation, the body produces toxins that can cause oxidative stress. When this oxidative stress builds up, it can damage cells or even destroy them in different parts of the body, including the central nervous system (CNS). Inflammation within your CNS can also cause oxidative stress, and oxidative stress may trigger more inflammation.

One way the body combats inflammation is through the Nrf2 pathway. This pathway is a complex communication system that defends cells against oxidative stress.

Although we don’t know exactly how TECFIDERA works against relapsing MS, researchers have learned that TECFIDERA leads to activation of the Nrf2 pathway. This may help defend against oxidative stress. Talk with your doctor to learn more about your treatment options.

Side effects

Does TECFIDERA have serious side effects?

Some serious side effects of TECFIDERA include:

  • allergic reactions
  • PML (a rare brain infection that usually leads to death or severe disability)
  • decreases in your white blood cell count
  • liver problems
  • herpes zoster infections (shingles), including central nervous system infections
  • other serious infections
  • severe gastrointestinal problems

What are the most common side effects of TECFIDERA?

Flushing and stomach problems are the most common side effects of TECFIDERA. Flushing symptoms are usually described as redness, itching, or rash. Stomach symptoms include nausea, vomiting, diarrhea, stomach pain, or indigestion.

Learn more about the most common side effects of TECFIDERA and how they tended to decrease over time in clinical trials.

What should I do if I experience common side effects?

If you're experiencing any of the common side effects of TECFIDERA, talk to your healthcare provider about trying the tips below:

  • Tips for flushing

Taking a non-coated aspirin (up to 325 mg) half an hour before taking TECFIDERA may help with flushing. Another tip that may help is taking TECFIDERA after a meal.

  • Tips for stomach problems

Taking TECFIDERA with food may help with stomach problems.* High-fat foods like peanut butter, cheese, or yogurt may be particularly helpful. If you decide to take TECFIDERA with food, it should be taken after you eat. Visit the USDA website for more about how fats fit into a healthy diet.

You can also ask your healthcare provider or pharmacist about over-the-counter medicines, like antacids, since that may help.* Read more about tips for handling the most common side effects.

*In a small 12-week study, people recorded their experience of managing stomach problems while on TECFIDERA. They found that taking it with food or over-the-counter medications could help.

How long do common side effects last?

In clinical trials, common side effects tended to happen earlier in treatment and usually decreased over time. Keep in mind that everyone is different and may react differently to the same medication.

What’s PML?

PML is a rare brain infection that usually leads to death or severe disability over a period of weeks or months. Tell your healthcare provider right away if you get any of these symptoms of PML:

  • weakness on one side of the body that gets worse
  • clumsiness in your arms or legs
  • vision problems
  • changes in thinking and memory
  • confusion
  • personality changes
Effectiveness

How effective is TECFIDERA?

In clinical studies, TECFIDERA was shown to:

How can I tell if TECFIDERA is working?

Talking to your healthcare provider about the results of your MRI could help with the management of your relapsing multiple sclerosis (MS). Lesions revealed on an MRI scan may help your healthcare provider determine how well your treatment is working.

Finding support

What kind of support does TECFIDERA offer?

If you’re living with relapsing multiple sclerosis (MS), know that you’re not alone. Biogen Support Services is here to help along the way. As soon as you’re prescribed brand-name TECFIDERA, we can provide help with:

  • Financial assistance
  • Navigating insurance
  • Learning more about your therapy

Remember, your healthcare team is always your best source of information.

What can I do if my insurance doesn't cover TECFIDERA?

At Biogen, our goal is for everyone to get the support they need so they can afford their brand-name TECFIDERA. Our Support Coordinators can work with you to understand your insurance coverage and medication cost and explore financial assistance options for your treatment. Call 1-800-456-2255 to learn more about what financial support resources are available for brand-name TECFIDERA with Biogen Support Services.

How can I find out if I’m eligible for the Biogen Copay Program*?

Biogen Support Coordinators can help identify potential options for financial assistance with your relapsing MS medication if you are:

  • Commercially insured
  • Government insured
  • Uninsured or underinsured

Call Biogen Support Services at 1-800-456-2255 to see if you’re eligible.

*Depending on your income or, in some cases, if your medication is obtained from an out-of-network provider, there may be an annual cap that limits the amount of assistance that you can receive over one year. Federal and state laws and other factors may prevent or otherwise restrict eligibility. People covered by Medicare, Medicaid, the VA/DoD, or any other federal plans are not eligible to enroll. You are eligible to enroll in the Biogen Copay Program for as long as it is offered and you are treated with a Biogen relapsing MS medication. The Biogen Copay Program is no longer available for TECFIDERA patients in the states of Massachusetts and California.

How can a Nurse Educator help me?

Nurse Educators are registered nurses, and many are MS-certified. Nurse Educators can:

  • Answer questions or provide information related to your relapsing MS and brand-name TECFIDERA
  • Provide ongoing phone support on how to take your medication and help manage common side effects
  • Review instructions from your healthcare provider and connect you with available resources

Biogen Support Services offers free access to Nurse Educators Monday-Friday from 8:30 AM to 8 PM ET. To reach one, call 1-800-456-2255.
Support is also available in Spanish.

TECFIDERA & GENERICS

Are generics available for TECFIDERA?

Yes. Your pharmacy could automatically substitute a generic treatment for your brand-name TECFIDERA, if your existing prescription doesnʼt specify "Dispense as Written (DAW)," or the wording required by your state regulations. This could affect your access to Biogen Support Services.

Patients who are prescribed a Biogen therapy are eligible for Biogen Support Services. Once you are prescribed a Biogen therapy, you have access to personalized support for as long as you are on treatment. This access includes one-on-one support with a Biogen Support Coordinator, who can help you understand your insurance coverage and medication costs. Nurse Educators are also available by phone 24/7 to offer support throughout your time on a Biogen treatment and answer any questions you may have.

What if I want to continue to receive support from Biogen Support Services?

Biogen offers options for relapsing multiple sclerosis (MS) treatment. Patients who are prescribed a Biogen therapy are eligible for Biogen Support Services. Once you are prescribed a Biogen therapy, you have access to personalized support.

How can I make sure I’m getting brand-name TECFIDERA from my healthcare provider and my specialty pharmacy?

There are three simple tips you can follow to help manage your brand-name TECFIDERA. It’s important to keep an open dialogue with your healthcare provider and specialty pharmacy to ensure your prescriptions, refills, and automatic refills are filled as discussed.

If you realize you’re not getting brand-name TECFIDERA, call your healthcare provider and inform them. You can also contact a Biogen Support Coordinator at 1-800-456-2255. They are ready to help manage your brand-name TECFIDERA.

Are generics available for TECFIDERA?

Yes. Your pharmacy could automatically substitute a generic treatment for your brand-name TECFIDERA, if your existing prescription doesnʼt specify "Dispense as Written (DAW)," or the wording required by your state regulations. This could affect your access to Biogen Support Services.

Patients who are prescribed a Biogen therapy are eligible for Biogen Support Services. Once you are prescribed a Biogen therapy, you have access to personalized support for as long as you are on treatment. This access includes one-on-one support with a Biogen Support Coordinator, who can help you understand your insurance coverage and medication costs. Nurse Educators are also available by phone 24/7 to offer support throughout your time on a Biogen treatment and answer any questions you may have.

What if I want to continue to receive support from Biogen Support Services?

Biogen offers options for relapsing multiple sclerosis (MS) treatment. Patients who are prescribed a Biogen therapy are eligible for Biogen Support Services. Once you are prescribed a Biogen therapy, you have access to personalized support.

How can I make sure I’m getting brand-name TECFIDERA from my healthcare provider and my specialty pharmacy?

There are three simple tips you can follow to help you manage your brand-name TECFIDERA. It’s important to keep an open dialogue with your healthcare provider and specialty pharmacy to ensure your prescriptions, refills, and automatic refills are filled as discussed.

If you realize you’re not getting brand-name TECFIDERA, call your healthcare provider and inform them. You can also contact a Biogen Support Coordinator at 1-800-456-2255. They are ready to help manage your brand-name TECFIDERA.