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Istradefylline Dosage

Medically reviewed by Drugs.com. Last updated on Oct 15, 2019.

Applies to the following strengths: 20 mg; 40 mg

Usual Adult Dose for Parkinson's Disease

Initial dose: 20 mg orally once a day
-Dose may be increased based on individual need and tolerability
Maintenance dose: 20 to 40 mg orally once a day
Maximum dose: 40 mg/day

Use: As adjunctive treatment to levodopa/carbidopa in patients with Parkinson's disease experiencing OFF episodes.

Renal Dose Adjustments

CrCl 15 to 89 mL/min: No adjustment recommended
CrCl less than 15 mL/min: Data not available

Liver Dose Adjustments

Mild hepatic impairment (Child-Pugh A): No adjustment recommended
Moderate hepatic impairment (Child-Pugh B): Maximum dose: 20 mg orally once a day
Severe hepatic impairment (Child-Pugh C): Avoid use

Dose Adjustments

Concomitant Use with Strong CYP450 3A4 Inhibitors:
-Maximum istradefyilline dose: 20 mg orally once a day

Concomitant Use with Strong CYP450 3A4 Inhibitors:
-Avoid istradefyilline use

Tobacco Use:
-For patients who smoke 20 or more cigarettes per day (or equivalent of another tobacco product): 40 mg orally once a day

Precautions

CONTRAINDICATIONS: None

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:
-Take orally once a day with or without food

General:
-This drug should be taken with levodopa/carbidopa.

Monitoring:
-Monitor for increased dyskinesias
-Monitor for hallucinations/psychotic behavior
-Question patients on intense urges

Patient advice:
-Patients should be instructed to read the US FDA-approved patient labeling (Patient Information).
-Patients should understand that this drug may cause dyskinesia, exacerbate preexisting dyskinesia, cause intense urges, and/or cause hallucinations or psychotic behavior; if any of these behaviors occur, they should be instructed to report them to their healthcare provider.
-Patients should understand that this drug may interact with other drugs including over-the-counter drugs, dietary supplements, and herbal products; they should be instructed to inform their health care provider of all medications they are taking, plan to take, or will stop taking.
-Patients should understand that tobacco products may cause this drug to be less effective and a higher dose may be needed if they smoke 20 or more cigarettes a day.
-Women of childbearing potential should be advised to use contraception during treatment.

Further information

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