Gilenya Side Effects

Generic name: fingolimod

Medically reviewed by Philip Thornton, DipPharm. Last updated on Feb 17, 2025.

Note: This document provides detailed information about Gilenya.

Applies to fingolimod: oral capsule, oral tablet disintegrating Side Effects associated with fingolimod. Some dosage forms listed on this page may not apply specifically to the brand name Gilenya.

Applies to fingolimod: oral capsule, oral tablet disintegrating.

Precautions

It is very important that your doctor check your or your child's progress at regular visits to make sure that this medicine is working properly. Blood and urine tests and tests for heart function may be needed to check for unwanted effects.

Symptoms of your MS may return and become worse after stopping treatment with this medicine. Do not stop using this medicine without checking first with your doctor.

Using this medicine while you are pregnant can harm your unborn baby. If you are a woman who can get pregnant, your doctor may do tests to make sure you are not pregnant before starting this medicine. Use an effective form of birth control to keep from getting pregnant during treatment with this medicine and for 2 months after the last dose. If you think you have become pregnant while using this medicine, tell your doctor right away.

This medicine may cause your or your child's heart rate to slow down, especially after taking the first dose. You or your child will be observed in a hospital or clinic for 6 hours for signs and symptoms of bradycardia (slow heartbeat). Symptoms may include chest pain or discomfort, lightheadedness, dizziness, or fainting, slow or irregular heartbeat, or unusual tiredness.

This medicine may increase your risk of developing infections, including a herpes infection or a serious brain infection called meningitis or progressive multifocal leukoencephalopathy. Avoid being near people who are sick or have infections while you are using this medicine. Wash your hands often. Also tell your doctor if you have ever had an infection that would not go away or an infection that kept coming back.

Fingolimod may cause a rare condition called immune reconstitution inflammatory syndrome (IRIS). This may occur after a person stops receiving this medicine after developing PML during treatment. Tell your doctor right away if you have an inflammatory reaction to an infection that includes mild burning, stinging, or tingling of the skin, or a feeling of heat, redness, or swelling of the skin.

While you are being treated with fingolimod (the active ingredient contained in Gilenya) and for 2 months after you stop treatment with it, do not have any immunizations (vaccines) without your doctor's approval. Your child should also have a complete immunization record before starting treatment with this medicine. Fingolimod may lower your or your child's body's resistance and the vaccine may not work as well or you might get the infection the vaccine is meant to prevent. In addition, you or your child should not be around other persons living in your household who receive live virus vaccines because there is a chance they could pass the virus on to you. Some examples of live vaccines include measles, mumps, influenza (nasal flu vaccine), poliovirus (oral form), rotavirus, and rubella. Do not get close to them and do not stay in the same room with them for very long. If you have questions about this, talk to your doctor.

This medicine may cause macular edema (swelling of the back of the eye), especially during the first 3 to 4 months of treatment. Check with your doctor right away if blurred vision, difficulty in reading, or any other change in vision occurs during or after treatment. Your doctor may want an eye doctor (ophthalmologist) to check your eyes.

This medicine may cause a serious nervous system problem called posterior reversible encephalopathy syndrome (PRES). Check with your doctor right away if you or your child have a sudden and severe headache, confusion, vision changes, or seizures with this medicine.

Tell your doctor right away if you have a cough, trouble breathing, chest tightness, or any type of breathing problem with this medicine. These could be symptoms of a serious lung problem.

Check with your doctor right away if you or your child have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, unusual tiredness or weakness, or yellow eyes or skin. These could be symptoms of a serious liver problem.

This medicine may cause a severe increase in disability, including worsening of MS symptoms (eg, blurred vision, difficulty controlling your bladder or bowels, trouble walking, swallowing, or speaking, numbness or tingling in your arms, legs, or face, muscle spasms) for at least 12 to 24 weeks after stopping the medicine. Talk to your doctor if you have concerns about this.

Your doctor will check your blood pressure on a regular basis while you are using this medicine. Tell your doctor right away if you have a severe headache, lightheadedness, or changes in your vision.

This medicine may increase your risk of having skin cancer (eg, basal cell carcinoma, melanoma) or lymphoma. Tell your doctor right away if you notice any skin nodules, patches, or open sores that do not quickly heal. Avoid exposure to sunlight. Wear sunscreen with a high sun protection factor. Do not use sunlamps or tanning beds.

This medicine may cause serious allergic reactions, including angioedema, which can be life-threatening and require immediate medical attention. Tell your doctor right away if you or your child have a rash, hives or itching skin, or large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of Gilenya

Along with its needed effects, fingolimod may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking fingolimod:

Other side effects of Gilenya

Some side effects of fingolimod may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to fingolimod: oral capsule, oral tablet disintegrating.

General adverse events

The most common adverse events were headache, influenza, diarrhea, back pain, liver transaminase elevations, and cough.^[Ref]

Cardiovascular

• Common (1% to 10%): Hypertension, first degree AV block, bradycardia
• Uncommon (0.1% to 1%): Symptomatic bradycardia, second degree AV block
• Rare (0.01% to 0.1%): Peripheral arterial occlusive disease
• Very rare (less than 0.01%): Hemophagocytic syndrome
• Frequency not reported: Heart rate decrease, Mobitz type I (Wenckebach) block, Mobitz type II block
• Postmarketing reports: Third degree AV block, AV block with junctional escape, transient asystole, peripheral arterial occlusive disease^[Ref]

Hepatic

• Very common (10% or more): ALT/AST increased (14%)
• Common (1% to 10%): Elevation in liver transaminases, GGT increased, hepatic enzyme increased, liver function test abnormal^[Ref]

In the majority of cases, elevations in liver enzymes occurred within 6 to 9 months and returned to normal within approximately 2 months following discontinuation of fingolimod.^[Ref]

Immunologic

• Very common (10% or more): Influenza viral infection (13%), sinusitis (10.9%), infections
• Common (1% to 10%): Herpes viral infection, bronchitis, gastroenteritis, tinea infection
• Uncommon (0.1% to 1%): Pneumonia
• Frequency not reported: Fatal herpetic infection, fatal varicella zoster virus infection^[Ref]

Infections occurred at a rate similar to placebo.^[Ref]

Nervous system

• Very common (10% or more): Headache (25%)
• Common (1% to 10%): Dizziness, paresthesia, migraine
• Rare (less than 0.1%): Posterior reversible encephalopathy syndrome, ischemic and hemorrhagic stroke
• Frequency not reported: Neurological atypical disorders
• Postmarketing reports: Syncope^[Ref]

Symptoms of posterior reversible encephalopathy syndrome included sudden onset of severe headache, altered mental status, visual disturbances, and seizure.^[Ref]

Gastrointestinal

• Very common (10% or more): Diarrhea (12%)^[Ref]

Hematologic

• Common (1% to 10%): Lymphopenia, leukopenia
• Uncommon (0.1% to 1%): Neutrophil count decreased^[Ref]

Ocular

• Common (1% to 10%): Vision blurred, eye pain
• Uncommon (0.1% to 1%): Macular edema^[Ref]

Macular edema occurred at a dramatically higher rate in patients with a history of uveitis.^[Ref]

Respiratory

• Very common (10% or more): Cough (10%)
• Common (1% to 10%): Dyspnea, reduction in diffusion lung capacity, reduction in FEV1^[Ref]

Musculoskeletal

• Very common (10% or more): Back pain (12%)^[Ref]

Dermatologic

• Common (1% to 10%): Alopecia, eczema, pruritus^[Ref]

Metabolic

• Common (1% to 10%): Weight decreased, blood triglycerides increased^[Ref]

Other

• Common (1% to 10%): Asthenia
• Postmarketing reports: Unexplained death^[Ref]

Psychiatric

• Common (1% to 10%): Depression
• Uncommon (0.1% to 1%): Depressed mood^[Ref]

Oncologic

• Frequency not reported: Lymphoma^[Ref]

Hypersensitivity

• Postmarketing reports: Rash, urticaria, angioedema

See also:

Frequently asked questions

• Gilenya vs Tecfidera. How do they compare?
• Can Gilenya cause high blood pressure?
• Can Gilenya cause weight gain?
• Can Gilenya cause headaches?
• Gilenya and the covid-19 vaccine, what should I know?
• What are the new drugs used for multiple sclerosis (MS)?
• How much does Gilenya cost?
• What happens when you stop taking Gilenya?
• Does Gilenya suppress the immune system?

Further information

Gilenya side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer