-certain antibiotics like clarithromycin
-certain medicines for cholesterol like atorvastatin, lovastatin, and simvastatin
-certain medicines for fungal infections like ketoconazole, itraconazole, or posaconazole
-certain medicines for seizures like carbamazepine, phenobarbital, phenytoin
-digoxin
-rifampin
-St. John''s wort

They need to know if you have any of these conditions:

-cigarette smoker
-liver disease
-mental illness
-an unusual or allergic reaction to istradefylline, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

Visit your health care professional for regular checks on your progress. Tell your health care professional if your symptoms do not start to get better or if they get worse. Do not stop taking except on your health care professional''s advice. You may develop a severe reaction. Your health care professional will tell you how much medicine to take.

There have been reports of increased sexual urges or other strong urges such as gambling while taking this medicine. If you experience any of these while taking this medicine, you should report this to your health care professional as soon as possible.

If you smoke, tell your health care professional if you notice this medicine is not working well for you. Talk to your health care professional if you decide to stop smoking.

Do not become pregnant while taking this medicine. Women should inform their health care professional if they wish to become pregnant or think they might be pregnant. There is a potential for serious side effects and harm to an unborn child. Talk to your health care professional for more information.

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.