The Effects of
Gilenya
on the Body

Fingolimod (Gilenya) is an oral drug used to treat relapsing-remitting multiple sclerosis (RRMS). This drug helps prevent white blood cells from circulating in the body. Most side effects from Gilenya are mild, but some side effects are serious.

Gilenya is an oral drug used to treat relapsing-remitting multiple sclerosis (RRMS). This drug helps prevent white blood cells from circulating in the body. As your white blood cell count goes down, this may calm your immune system. The result is that the drug may prevent white blood cells from entering the central nervous system and causing the damaging effects of multiple sclerosis (MS).

Two clinical studies were described in the FDA label for Gilenya. The first study lasted two years. Those who took Gilenya had fewer relapses than those who didn’t take it. Those who took Gilenya also had less than one-third the number of new or enlarged lesions when they were studied on MRI scans. In the second study, participants took either Gilenya or interferon beta-1a. When those who took Gilenya were compared with those who took interferon beta-1a, the people taking Gilenya had half the relapse rate and also 40 percent fewer new or enlarged lesions.

The dosage of Gilenya is one capsule per day. It can be taken with food. The drug level in your body will slowly increase and reach its maximum in one or two months.

Neurological Effects

A headache is a fairly common side effect of Gilenya. You should call 911 or go to the emergency room if you have a severe headache, vision changes, or a seizure. This is a medical emergency.

Some people may have vision changes after starting Gilenya, such as blurred vision. Call your doctor right away if this happens. These changes usually stop once you have quit using the drug. Don’t stop taking Gilenya without first speaking with your doctor about it.

A very rare side effect of Gilenya is progressive multifocal leukoencephalopathy (PML). PML is a serious brain infection caused by a virus. The symptoms of PML include:

• weakness or clumsiness on one side of the body
• changes in vision or thinking
• confusion

You should see your doctor right away if you think you have PML.

Cardiovascular System

Slowed Heart Rate

Your heart rate can slow down with this drug. You will take the first dose of Gilenya at your doctor’s office so that your heart rate can be monitored. A reduced heart rate can last for a few days or weeks, but it usually returns to normal.

Drugs that slow the heart rate can be dangerous if taken with Gilenya. Some of these include:

• beta blockers, like carvedilol, atenolol, and others
• digoxin (Lanoxin, Digox)
• diltiazem (Dilt-cd, Cardizem)
• calcium channel blockers, like verapamil (Calan, Covera-HS, Verelan)

Alcoholdoesn’t actually interact with Gilenya, but it can dehydrate you and increase your risk of changes in the way your heart beats. Adding this effect to Gilenya’s effect on the heart could be risky.  

Endocrine System

Gilenya can increase liver enzymes and cause liver damage.Call your doctor if you have the symptoms of liver damage, which include:

• nausea
• vomiting
• abdominal pain
• fatigue
• a loss of appetite
• yellowing of the eyes or skin
• dark urine 

Digestive System

Gilenya may cause diarrhea or abdominal pain. Speak with your doctor if you have these symptoms.

Immune System

Gilenya changes the way your immune systems functions. People taking Gilenya have an increased risk of influenza, or the flu, and other infections because of this change in your immune system.

Vaccines interact with Gilenya because the immune response may be poor and you risk infection. Talk to your doctor and pharmacist about Gilenya and vaccines before you start taking the drug.

Drugs that affect your immune system can interact with Gilenya. These include:

• natalizumab (Tysabri)
• teriflunomide (Aubagio)
• mitoxantrone (Novantrone)

Corticosteroids, like prednisone, further reduce your immune function while you’re taking Gilenya. Tell your doctor if you’re taking corticosteroids.