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Generic name: istradefyllineIS-tra-DEF-i-lin ]
Drug class: Miscellaneous antiparkinson agents

Medically reviewed by Judith Stewart, BPharm. Last updated on Aug 22, 2023.

What is Nourianz?

Nourianz is is an adenosine receptor antagonist. Adenosine receptors are involved with the regulation of motor (muscle) behaviour.

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

Nourianz is a prescription medicine and is supplied as a 20mg or 40mg tablet.


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.

Before taking this medicine

To make sure Nourianz is safe for you, 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.

How should I take Nourianz?

Take Nourianz exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

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

You may take Nourianz with or without food.

Store at room temperature away from moisture and heat.

Dosing information

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.

What happens if I miss a dose?

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.

What happens if I overdose?

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

What to avoid

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

Nourianz side effects

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

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 this medicine. Talk with your doctor if this occurs.

Common Nourianz side effects may include:

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.

What other drugs will affect Nourianz?

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 interact with 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.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Nourianz only for the indication prescribed.

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