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Generic name: dalfampridine (dal FAM pri deen)
Brand name: Ampyra
Drug class: Miscellaneous central nervous system agents

Medically reviewed by Last updated on Jul 29, 2021.

What is Ampyra?

Ampyra (dalfampridine) is a potassium channel blocker.

Ampyra is a prescription medicine used to improve walking in adults with multiple sclerosis (MS).

It is not known if Ampyra is safe or effective in children less than 18 years old.


Ampyra can cause a seizure (convulsions), even if you have never had one before. Taking too much dalfampridine may increase your risk of seizure. Kidney problems may also increase your risk. Your kidney function may need to be tested before you start taking this medicine.

Stop taking Ampyra and call your doctor at once if you a seizure, pain or burning when you urinate, problems with your balance, numbness or tingly feeling, or a relapse of your MS symptoms.

High doses of dalfampridine may increase your risk of seizure. Do not take more than 2 tablets in a 24-hour period. Do not use a tablet that has been broken or crushed. A broken tablet can release too much of the drug at one time.

Before taking this medicine

You should not use Ampyra if you are allergic to dalfampridine, or if you've ever had:

  • a seizure (convulsions); or

  • moderate to severe kidney disease.

Tell your doctor if you have ever had:

  • kidney disease; or

  • if you also take a form of this medicine obtained from a compounding pharmacy (fampridine, or 4-aminopyridine).

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

You should not breast-feed while using dalfampridine.

Ampyra is not approved for use by anyone younger than 18 years old.

How should I take Ampyra?

Take Ampyra exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed. High doses of dalfampridine may increase your risk of seizure.

Before you start treatment with dalfampridine, your doctor may perform tests to check your kidney function.

Ampyra is usually taken once every 12 hours. Follow your doctor's dosing instructions very carefully. Do not take more than 2 tablets in a 24-hour period.

You may take this medicine with or without food.

Swallow the tablet whole and do not crush, chew, or break it. Breaking the pill may cause too much of the drug to be released at one time which can increase your risk of a seizure.

Do not use a tablet that has been crushed or broken.

Your kidney function may need to be checked often.

Store at room temperature away from moisture and heat.

Throw away any leftover medicine after the expiration date on the label has passed.

Dosing information

Usual Adult Dose for Multiple Sclerosis:

Maximum dose: 10 mg orally every 12 hours

-This drug may be taken with or without food.
-Tablets should be swallowed whole, and not divided, crushed, chewed, or dissolved.
-Patients should not take double or extra doses if a dose is missed.

Use: To improve walking in adult patients with multiple sclerosis (MS) demonstrated by an increase in walking speed

What happens if I miss a dose?

Skip the missed dose and use your next dose at the regular time. Do not use 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.

Overdose can cause confusion or seizures.

What to avoid

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

Ampyra side effects

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

Stop taking this medicine and call your doctor at once if you have:

  • a seizure (convulsions);

  • pain or burning when you urinate;

  • numbness, burning pain, or tingly feeling;

  • problems with balance; or

  • relapse or worsening of MS symptoms.

Common Ampyra 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 Ampyra?

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may interact with dalfampridine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

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

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