Diroximel fumarate is used to treat relapsing forms of multiple sclerosis in adults (including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease).

Diroximel fumarate may also be used for purposes not listed in this medication guide.

You should not use diroximel fumarate if you have had a severe allergic reaction to diroximel fumarate, or if you also use dimethyl fumarate (Tecfidera).

Your doctor will perform blood tests to make sure you do not have conditions that would prevent you from safely using diroximel fumarate.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Swallow the capsule whole and do not crush, chew, break, or open it.

If you take diroximel fumarate with food, avoid foods that are high in calories or fat. Your meal or snack should not contain more than 700 calories or more than 30 grams of fat.

Do not drink alcohol when you take your diroximel fumarate dose.

Diroximel fumarate may cause flushing (a sudden sense of warmth or tingling), which should decrease over time. If this side effect is bothersome, ask your doctor about taking aspirin to help prevent flushing.

Store at room temperature away from moisture and heat.

Diroximel fumarate can have long lasting effects on your body. You may need frequent medical tests while using diroximel fumarate and for a short time after your last dose.

Usual Adult Dose for Multiple Sclerosis:

Initial dose: 231 mg orally twice a day for 7 days
Maintenance dose: 462 mg orally twice a day

Use: For the treatment of relapsing forms of multiple sclerosis, to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease

You should not use this medicine if:

• you have had a severe allergic reaction to diroximel fumarate or dimethyl fumarate (Tecfidera); or

• you also use dimethyl fumarate.

Tell your doctor if you have ever had:

• liver disease;

• kidney disease;

• infections; or

• low white blood cell (WBC) counts.

Tell your doctor if you are pregnant or breastfeeding.

Diroximel fumarate is not approved for use by anyone younger than 18 years old.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Avoid high-fat, high-calorie meals or snacks while taking diroximel fumarate to reduce certain side effects.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Diroximel fumarate may cause a serious brain infection that can lead to disability or death. Call your doctor right away if you have problems with speech, thought, vision, or muscle movement. These symptoms may start gradually and get worse quickly.

Also call your doctor at once if you have:

• liver problems--loss of appetite, stomach pain (upper right side), tiredness, dark urine, jaundice (yellowing of the skin or eyes);

• signs of infection--fever, chills, sweating, cough, shortness of breath, headache, neck stiffness, increased sensitivity to light, nausea, vomiting; or

• symptoms of herpes virus--flu-like symptoms, cold sores around your mouth, tingly or painful blistering rash, burning pain in your thigh or lower back.

Common side effects of diroximel fumarate may include:

• indigestion, nausea, vomiting, stomach pain;

• skin rash, itching, or redness;

• diarrhea; or

• flushing (sudden warmth, redness, or tingly feeling).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Other drugs may affect diroximel fumarate, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.