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Generic Name: dalfampridine (dal FAM pri deen)
Brand Name: Ampyra

What is dalfampridine?

Dalfampridine is a potassium channel blocker.

Dalfampridine is used to improve walking in patients with multiple sclerosis (MS).

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

Important Information

Dalfampridine 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.

You should not use dalfampridine if you have moderate to severe kidney disease, or if you have ever had a seizure (convulsions).

Stop taking dalfampridine and call your doctor right away if you have a seizure.

Before taking this medicine

You should not use dalfampridine if you are allergic to it, or if:

  • you have had a seizure (convulsions); or

  • you have moderate to severe kidney disease.

To make sure dalfampridine is safe for you, tell your doctor if you have:

  • 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.

It is not known whether dalfampridine passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

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

How should I take dalfampridine?

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

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended. High doses of dalfampridine may increase your risk of seizure.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

Dalfampridine is usually taken once every 12 hours. Follow your doctor's dosing instructions very carefully.

Do not crush, chew, or break an extended-release tablet. Swallow it whole. Do not dissolve the tablet in liquid. Breaking or dissolving the pill may cause too much of the drug to be released at one time which can increase your risk of a seizure.

Dalfampridine may be taken with or without food.

Do not take more than 2 tablets in a 24-hour period.

To be sure this medicine is not causing harmful effects, 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.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

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

Overdose can cause confusion, problems with thinking or memory, tremors, sweating, or seizures.

What should I avoid while taking dalfampridine?

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

Dalfampridine side effects

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

Stop taking dalfampridine 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 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.

See also: Side effects (in more detail)

Dalfampridine dosing information

Usual Adult Dose for Multiple Sclerosis:

Maximum recommended dose: 10 mg every 12 hours, taken with or without food

Patients should not take double or extra doses if a dose is missed.

Tablets should only be taken whole. Tablets should not be divided, crushed, chewed, or dissolved.

Usual Geriatric Dose for Multiple Sclerosis:

Maximum recommended dose: 10 mg every 12 hours, taken with or without food

Patients should not take double or extra doses if a dose is missed.

Tablets should only be taken whole. Tablets should not be divided, crushed, chewed, or dissolved.

A population pharmacokinetic analysis showed that dalfampridine clearance modestly decreased with increasing age, but not sufficiently to necessitate a modification of dose.

What other drugs will affect dalfampridine?

Other drugs may interact with dalfampridine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about dalfampridine.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 5.01.

Date modified: February 01, 2018
Last reviewed: February 14, 2017