Riluzol

riluzole /ril·u·zole/ (ril´u-zōl) a compound used to prolong survival time in the treatment of amyotrophic lateral sclerosis.

Riluzole (Rilutek)

The first drug approved in the United States for the treatment of ALS.

Mentioned in: Amyotrophic Lateral Sclerosis

riluzole,

a glutamate antagonist.

indication This drug is used to treat amyotropic lateral sclerosis.

contraindication Known hypersensitivity to this drug prohibits its use.

adverse effects Neutropenia and exfoliative dermatitis are life-threatening effects. Other adverse effects are nausea, vomiting, dyspepsia, anorexia, diarrhea, flatulence, stomatitis, dry mouth, hypertonia, depression, dizziness, insomnia, somnolence, vertigo, pruritus, eczema, alopecia, decreased lung function, rhinitis, increased cough, hypertension, tachycardia, phlebitis, palpitations, postural hypertension, urinary tract infection, and dysuria.

amyotrophic lateral sclerosis

a progressive neurologic disease characterized by degeneration of cell bodies of the lower motor neurons in the gray matter of the anterior horns of the spinal cord, some brainstem motor neurons, and the pyramidal tracts. Called also Lou Gehrig's disease.

The disease presents in adulthood, usually between the ages of 40 and 70, and affects men two to three times more often than women. The initial symptom is weakness of skeletal muscles, especially in the limb. As the disease progresses the patient has difficulty swallowing and talking, with dyspnea as the accessory muscles of respiration are affected. Eventually muscles atrophy and the patient becomes a functional quadriplegic. Mentation is not affected, so that the patient remains alert and aware of functional loss and the inevitable outcome. Although there may be periods of remission, the disease usually progresses rapidly, with death in 2 to 5 years. The cause of ALS is not known and there is no cure. Treatment is intended to provide symptomatic relief, prevent complications, and maintain optimal function as long as possible.

Patient Care. For the most part, ALS patients are cared for at home and are hospitalized only for diagnosis, when severe dysphagia demands an esophagostomy or gastrostomy for feeding, or when medical treatment is necessary for acute respiratory problems.

Intervention is planned and implemented according to each patient's needs at specific times during the course of the illness. In general, the major problems encountered are those related to (1) dysphagia and the need to meet nutritional requirements and avoid aspiration, (2) dyspnea and maintenance of blood gases within normal range, (3) aphasia and impaired verbal communication, (4) weakness, impaired mobility, and activity intolerance, (5) constipation, (6) pain and discomfort due to muscle cramps, and (7) alteration in self-concept and body image.

The patient and family also will need assistance in managing home care, coping with the effects of the illness, and maintaining optimal functioning in the patient. Community health nurses and home health care professionals and paraprofessionals should be available to provide a variety of services including physical therapy, occupational therapy, social services, mental health care, and medical and nursing care.

A resource agency that can provide assistance and information to ALS patients and their families is the Amyotrophic Lateral Sclerosis Association, 21021 Ventura Blvd., Suite 321, Woodland Hills, CA 91364-2206, (800) 782–4747; http://www.alsa.org.

riluzole (ril´

zōl´),

n brand name: Rilutek;
drug class: glutamate antagonist;
action: inhibits presynaptic release of glutamic acid in central nervous system;
use: treatment of amyotrophic lateral sclerosis (Lou Gehrig disease).

riluzole

Rilutek

Pharmacologic class: Glutamate antagonist

Therapeutic class: Amyotrophic lateral sclerosis (ALS) agent

Pregnancy risk category C

Action

Unknown. Thought to inhibit amino acid accumulation on motor neurons of CNS, improving nerve impulse transmission.

Availability

Tablets: 50 mg

⊘Indications and dosages

➣ ALS

Adults: 50 mg P.O. q 12 hours

Off-label uses

• Cervical dystonia
• Huntington's disease

Contraindications

• Hypersensitivity to drug or its components

Precautions

Use cautiously in:
• hepatic or renal insufficiency, neutropenia, febrile illness
• elderly patients
• female patients and Japanese patients (may have decreased metabolic capacity to eliminate drug)
• pregnant or breastfeeding patients
• children.

Administration

• Give at least 1 hour before or 2 hours after a meal to maximize absorption.

Route	Onset	Peak	Duration
P.O.	Unknown	Unknown	Unknown

Adverse reactions

CNS: headache, dizziness, drowsiness, asthenia, hypertonia, depression, insomnia, malaise, vertigo, circumoral paresthesia

CV: hypertension, orthostatic hypotension, tachycardia, palpitations, peripheral edema, phlebitis, cardiac arrest

EENT: rhinitis, sinusitis, oral candidiasis

GI: nausea, vomiting, diarrhea, abdominal pain, dyspepsia, flatulence, stomatitis, dry mouth, anorexia

GU: urinary tract infection, dysuria

Hematologic: neutropenia

Musculoskeletal: back pain, joint pain

Respiratory: decreased lung function, increased cough, pneumonia

Skin: pruritus, eczema, alopecia, exfoliative dermatitis

Other: tooth disorders, weight loss

Interactions

Drug-drug. Allopurinol, methyldopa, sulfasalazine: increased risk of hepatotoxicity

CYP450-1A2 inducers (such as omeprazole, rifampin): increased riluzole elimination

CYP450-1A2 inhibitors (such as amitriptyline, phenacetin, quinolones, theophylline): decreased riluzole elimination

Drug-diagnostic tests. Alanine aminotransferase, aspartate aminotransferase, bilirubin, gamma-glutamyltransferase: increased levels

Drug-food. High-fat foods: decreased riluzole absorption

Drug-behaviors. Alcohol use: increased risk of hepatotoxicity

Patient monitoring

• Monitor liver function tests and CBC.
• Assess vital signs and cardiovascular status, particularly for hypertension, orthostatic hypotension, and peripheral edema.
• Closely monitor respiratory status for decreased lung function and pneumonia.
• Monitor weight, nutritional status, and hydration.
• Closely monitor females and patients of Japanese origin, who are at increased risk for adverse reactions.

Patient teaching

• Tell patient to take 1 hour before or 2 hours after a meal, at same time each day.
• Instruct patient to take his temperature regularly and report fever.
☞ Teach patient to immediately report arm or leg swelling, difficulty breathing, and other signs of decreased lung function.
• Advise patient to minimize GI upset by eating small, frequent servings of food and drinking plenty of fluids.
• Caution patient to avoid high-fat foods and alcohol.
• Instruct patient to move slowly when sitting up or standing, to avoid dizziness from sudden blood pressure decrease.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, and behaviors mentioned above.