Istradefylline is given with levodopa and carbidopa to treat "wearing-off" episodes (muscle stiffness, loss of muscle control) in people with Parkinson's disease.

Istradefylline may also be used for purposes not listed in this medication guide.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Istradefylline is usually taken once per day. Follow your doctor's dosing instructions very carefully.

You may take istradefylline with or without food.

Store at room temperature away from moisture and heat.

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.

Tell your doctor if you have ever had:

• abnormal muscle movements;

• mental illness or psychosis;

• liver disease; or

• if you smoke.

Tell your doctor if you are pregnant or breastfeeding.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Unless your doctor tells you otherwise, continue your normal diet.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Istradefylline may cause serious side effects. Call your doctor at once if you have:

• uncontrolled or involuntary muscle movements;

• unusual thoughts or behavior;

• confusion, hallucinations; or

• risk-taking behavior, being impulsive.

You may have increased sexual urges, unusual urges to gamble, or other intense urges while taking istradefylline. Talk with your doctor if this occurs.

Common side effects of istradefylline may include:

• involuntary muscle movements;

• hallucinations;

• dizziness;

• nausea, constipation; or

• sleep problems (insomnia).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Other drugs may affect istradefylline, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.