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Riluzole Side Effects

In Summary

Commonly reported side effects of riluzole include: asthenia, nausea, and increased serum alanine aminotransferase. Other side effects include: vomiting. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to riluzole: oral suspension, oral tablet

Side effects requiring immediate medical attention

Along with its needed effects, riluzole 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 riluzole:

Less common

  • Bladder pain
  • bloody or cloudy urine
  • blurred vision
  • chills
  • cough
  • dark urine
  • diarrhea
  • difficult, burning, or painful urination
  • fast, pounding, or irregular heartbeat or pulse
  • fever
  • frequent urge to urinate
  • general feeling of discomfort or illness
  • headache
  • increased cough
  • itching skin
  • joint pain
  • loss of appetite
  • lower back or side pain
  • muscle aches and pains
  • nausea
  • nervousness
  • persistent loss of appetite or weight loss
  • pounding in the ears
  • right upper quadrant tenderness
  • runny nose
  • shivering
  • slow heartbeat
  • sore throat
  • trouble sleeping
  • unusual tiredness or weakness
  • vomiting
  • yellow eyes or skin

Incidence not known

  • Black, tarry, stools
  • decreased frequency or amount of urine
  • difficult breathing
  • increased thirst
  • nausea
  • pale skin
  • swelling of the face, fingers, or lower legs
  • ulcers, sores, or white spots in the mouth
  • unusual bleeding or bruising
  • weight gain

Get emergency help immediately if any of the following symptoms of overdose occur while taking riluzole:

Symptoms of overdose

  • Agitation
  • back pain
  • bluish-colored lips, fingernails, or palms
  • blurred vision
  • coma
  • confusion
  • dark urine
  • difficulty breathing
  • dizziness or lightheadedness
  • drowsiness
  • fever
  • headache
  • irritability
  • memory loss
  • pale skin
  • rapid heart rate
  • seeing, hearing, or feeling things that are not there
  • seizures
  • sore throat
  • stiff neck
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vomiting

Side effects not requiring immediate medical attention

Some side effects of riluzole 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:

More common

  • Lack or loss of strength

Less common

  • Difficulty moving
  • dizziness or lightheadedness
  • dry mouth
  • excess air or gas in the stomach or bowels
  • feeling of constant movement of self or surroundings
  • full feeling
  • muscle stiffness
  • passing gas
  • rapid weight gain
  • sensation of spinning
  • skin rash, encrusted, scaly and oozing
  • sleepiness or unusual drowsiness
  • stomach pain
  • tingling of the hands or feet
  • unusual weight gain or loss

For Healthcare Professionals

Applies to riluzole: oral suspension, oral tablet

General

The most commonly reported adverse reactions have included asthenia, nausea, dizziness, decreased lung function, and abdominal pain.[Ref]

Hepatic

In clinical trials, ALT elevations above 5 times the upper limit of normal (5 X ULN) were reported in 2% of patients, about 50% had at least 1 elevated ALT, and 8% had at least one elevated ALT level above 3 x ULN. Drug-induced hepatic injury, including fatalities, have been reported.

Study data indicate that Asian patients may be more susceptible to liver function test abnormalities; 3.2% (194/5995) of Asian patients and 1.8% (100/5641) of Caucasian patients experienced liver function test abnormalities.[Ref]

Very common (10% or more): At least 1 ALT elevation of above upper limit of normal (ULN)

Common (1% to 10%): ALT elevation above 5 x ULN

Rare (0.01% to 0.1%): Hepatitis, jaundice, hepatocellular damage

Frequency not reported: Drug-induced hepatic injury

Postmarketing reports: Acute hepatitis and icteric toxic hepatitis[Ref]

Hematologic

Uncommon (0.1% to 1%): Anemia

Rare (0.01% to 0.1%): Erythropenia, leucopenia, thrombocytopenia

Very rare (less than 0.01%): Neutropenia[Ref]

There have been 3 reports (n=5000) of marked neutropenia where absolute neutrophil count was less than 500/mm3, all within first 2 months of treatment. In one case, neutrophil counts rose on continued treatment. In a second case, counts rose after therapy was stopped. A third case was associated with marked anemia with uncertain etiology[Ref]

Respiratory

Common (1% to 10%): Decreased lung function, increased cough,

Uncommon (0.1% to 1%): Respiratory failure, interstitial lung disease

Rare (0.01% to 0.1%): Asphyxia, respiratory distress.

Frequency not reported: Hypersensitivity pneumonitis

Gastrointestinal

Very common (10% or more): Nausea (16%)

Common (1% to 10%): Abdominal pain, vomiting, dry mouth, flatulence

Uncommon (0.1% to 1%): Pancreatitis

Rare (0.01% to 0.1%): Gastrointestinal disorder, gastric ulcer, gastrointestinal hemorrhage, gastrointestinal irritation, melena[Ref]

Nervous system

Common (1% to 10%): Dizziness, circumoral paresthesia, somnolence[Ref]

In clinical trials, the incidence of dizziness was greater in females than males (11% vs 4%). There was no difference in rates of adverse reactions leading to discontinuation between genders.[Ref]

Hypersensitivity

Very rare (less than 0.01%): Angioedema

Frequency not reported: Anaphylaxis

Psychiatric

Common (1% to 10%): Insomnia

Rare (0.01% to 0.1%): Completed suicide, confusion, delirium, hallucination, personality change due to a general medical condition

Very rare (less than 0.01%): Amnesia

Renal

Postmarketing reports: Renal tubular impairment

Musculoskeletal

Common (1% to 10%): Arthralgia[Ref]

Cardiovascular

Common (1% to 10%): Hypertension, tachycardia, peripheral edema

Rare (0.01% to 0.1%): Angina unstable, atrial fibrillation, cardiac failure

Very rare (less than 0.01%): Arrhythmia

Metabolic

Rare (0.01% to 0.1%): Dehydration

Very rare (less than 0.01%): Hyponatremia

Other

Very common (10% or more): Asthenia (19%)

Common (1% to 10%): Vertigo, malaise, pyrexia

Dermatologic

Common (1% to 10%): Pruritus, eczema

Rare (0.01% to 0.1%): Dermatitis

Genitourinary

Common (1% to 10%): Urinary tract infection

References

1. "Product Information. Rilutek (riluzole)." Rhone-Poulenc Rorer, Collegeville, PA.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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