Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Rilutek (Riluzole). If you are concerned about side effects, discuss the risks and benefits of Rilutek (Riluzole) with your doctor.

The following side effects have been reported by at least 1% of people taking Rilutek (Riluzole). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• change in appetite
• Constipation
• dizziness
• drowsiness
• fatigue
• headache
• heartburn
• nausea
• pain
• rash
• stomach pain or upset
• tremor
• trouble sleeping
• weakness or loss of energy

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• depressed mood
• Diarrhea
• Fever
• irregular heartbeat
• mouth sores
• swelling of hands or feet
• vomiting

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a serious allergic reaction (e.g., swelling of face or throat, Hives, or difficulty breathing or shortness of breath)
• signs of liver problems (e.g., dark urine, yellowing of skin or eyes, abdominal swelling, general discomfort, itchiness, nausea, vomiting)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Rilutek (Riluzole).

Each white, capsule-shaped, film coated tablet, engraved with "RPR 202" on one side, contains Rilutek (Riluzole) 50 mg. Nonmedicinal ingredients: anhydrous colloidal silica, anhydrous dibasic calcium phosphate, croscarmellose sodium, hydroxypropyl methylcellulose, magnesium stearate, microcrystalline cellulose, polyethylene glycol 6000, and titanium dioxide.

Do not take this mediction if you:

• are allergic to Rilutek (Riluzole) or to any of the ingredients of the medication
• are pregnant or breast-feeding
• have liver disease or elevated liver function tests

There may be an interaction between Rilutek (Riluzole) and any of the following:

• alcohol
• Allopurinol
• anticonvulsants (e.g., carbemazepine)
• Amitriptyline
• caffeine
• cigarette smoke
• methyldopa
• Omeprazole
• quinolone antibiotics (e.g., ciprofloxacin, levofloxacin)
• rifampin
• Sulfasalazine
• tacrine
• Theophylline

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Rilutek (Riluzole). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Rilutek (Riluzole).

Alcohol: Limit your consumption of alcohol while taking Rilutek (Riluzole). Rilutek (Riluzole) may cause liver problems, and alcohol may increase the risk of liver problems.

Blood cell counts: Rilutek (Riluzole) may cause neutropenia (low white blood cell count), which can mean your immune system is weak. If you develop a fever, talk to your doctor as soon as possible. Your doctor will also perform blood tests regularly to monitor your blood cell counts.

Dizziness and drowsiness: Rilutek (Riluzole) can cause dizziness, Vertigo, or drowsiness in some people. Do not drive or operate machines until you now how Rilutek (Riluzole) affects you.

Kidney problems: If you have kidney problems, discuss with your doctor how Rilutek (Riluzole) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Rilutek (Riluzole), and whether any special monitoring is needed

Liver problems: Rilutek (Riluzole) can cause liver injury. Your doctor will perform tests regularly to monitor your liver function. If you experience any symptoms of liver damage (e.g., yellowing of skin or eyes, darkened urine, itchiness, abdominal swelling, loss of appetite, nausea, vomiting, fever), contact your doctor immediately. If you have liver disease or unexplained abnormal liver function test results, do not use Rilutek (Riluzole).

Pregnancy: The medication should not be used during pregnancy. If you become pregnant while taking Rilutek (Riluzole), contact your doctor immediately.

Breast-feeding: It is not known if Rilutek (Riluzole) passes into breast milk. Rilutek (Riluzole) should not be used by women who are breast-feeding.

Children: The safety and effectiveness of using Rilutek (Riluzole) have not been established for children.