Drug Detail:Istradefylline (Istradefylline [ is-tra-def-i-lin ])
Drug Class: Miscellaneous antiparkinson agents
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
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.
