Professional Information

Add to list

Comments

Riluzole

Pronouncation: (RILL-you-zole)
Class: CNS agent

Trade Names:
Rilutek
- Tablets 50 mg

Pharmacology

Feedback for Riluzole

As a treatment for...	Avg User Ratings [?]
Amyotrophic Lateral Sclerosis	Be the first to rate it 0 comments

Compare with other drugs.

Unknown; however, the following properties may be related to effects: inhibits glutamate release; inactivates voltage-dependent sodium channels; interferes with intra-cellular events following transmitter binding at excitatory amino acid receptors. These effects may protect neural tissues against degenerative changes.

Pharmacokinetics

Absorption

Well absorbed (about 90%). Oral bioavailability is about 50%. High fat meals decrease absorption, decrease AUC about 20% and peak blood levels by about 45%. Steady state is less than 5 days.

Distribution

Protein binding is 96%, mainly to albumin and lipoproteins. Penetrates brain readily.

Metabolism

Extensively metabolized to 6 major and a number of minor metabolites via CYP-450 dependent hydroxylation and glucuronidation. CYP-450 1A2 is the main isoenzyme involved in N-hydroxylation.

Elimination

Eliminated in urine (more than 85% glucuronide metabolites; 2% unchanged) and small amount in feces. T _½ is 12 h (after multiple dosing).

Special Populations

Renal Function Impairment

Reduced clearance of riluzole and its metabolites leading to higher plasma levels.

Hepatic Function Impairment

Reduced clearance of riluzole and its metabolites, leading to higher plasma levels.

Elderly

Age-related decreased renal function will give higher plasma levels of riluzole and metabolites.

Gender

CYP1A2 activity has been reported to be lower in women and may result in higher blood concentrations and metabolites.

Race

Clearance of drug in Japanese subjects was found to be 50% lower; may possess a lower capacity (oxidative or conjugative) for metabolizing riluzole.

Smoking

Induces CYP1A2 and will eliminate riluzole faster; no information on need to adjust dose in these patients.

Indications and Usage

Treatment of patients with amyotrophic lateral sclerosis (ALS; Lou Gehrig disease).

Contraindications

Standard considerations.

Dosage and Administration

Adults

PO 50 mg every 12 h.

Drug Interactions

Caffeine, theophylline, amitriptyline, quinolones

May reduce riluzole elimination.

Cigarette smoke, rifampin, omeprazole

May enhance riluzole elimination.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Hypertension; tachycardia; palpitations; peripheral edema.

CNS

Headache; hypertonia; depression; dizziness; insomnia; somnolence; vertigo; circumoral paresthesia; aggravation reaction; agitation; tremor.

Dermatologic

Pruritus; eczema; alopecia; exfoliative dermatitis.

EENT

Rhinitis; sinusitis.

Hepatic

Abnormal LFTs.

GI

Nausea; vomiting; dyspepsia; anorexia; diarrhea; constipation; flatulence; abdominal pain; stomatitis; dry mouth; oral moniliasis.

Genitourinary

Urinary tract infection; dysuria.

Metabolic

Weight loss.

Respiratory

Decreased lung function; cough.

Miscellaneous

Asthenia; arthralgia; back pain; malaise.

Precautions

Monitor

Measure serum aminotransferases before and during therapy. Evaluate serum SGPT levels every month during the first 3 mo of treatment, every 3 mo during the remainder of the first yr and periodically thereafter.

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established.

Elderly

Age-related compromised renal and hepatic function may cause a decrease in clearance of riluzole.

Renal Function

Use with caution in patients with renal impairment.

Hepatic Function

Use with caution in patients with current evidence or history of abnormal liver function indicated by significant elevations of liver enzymes. Baseline elevations of several LFTs (especially elevated bilirubin) should preclude use of riluzole.

Special Risk Patients

Females and Japanese patients may possess a lower metabolic capacity to eliminate riluzole as compared to males and Caucasian subjects, respectively.

Patient Information

Instruct patient to take medication 30 min before or 2 h after a meal.
Take with a full glass of water.
Instruct patient to take medicine at same time each day. If a dose is missed, take the next dose as originally planned.
Instruct patient not to change dose or discontinue medication without consulting health care provider. Larger than prescribed doses do not increase effectiveness, but do increase the side effects.
Have patient report any serious side effects to health care provider, including: asthenia, nausea, dizziness, diarrhea, decreased level of consciousness, respiratory distress.
Inform patient of need for frequent laboratory tests while taking medication. Be sure to keep appointments.
Instruct patient to report any fevers to health care provider.
Instruct patient to avoid drinking alcohol in excess while taking this medication.
Advise patient that drug may cause dizziness, vertigo, or somnolence and not to drive or operate machinery until patient has gained enough experience to gauge whether or not it affects mental or motor performance adversely.