November 30, 2015
Recommended Topic Related To:


"Among people with early-stage multiple sclerosis (MS), those with higher blood levels of vitamin D had better outcomes during 5 years of follow-up. Identifying and correcting vitamin D insufficiency could aid in the early treatment of MS.



Ampyra Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

Ampyra (dalfampridine) Extended-Release is a potassium channel blocker used to improve walking in patients with multiple sclerosis (MS). Common side effects include headache, dizziness, insomnia, nausea, constipation, upset stomach, weakness, back pain, stuffy nose, sinus pain, sore throat, or mild skin itching.

The maximum recommended dose of Ampyra is one 10 mg tablet twice daily, taken with or without food, and should not be exceeded. Doses should be taken approximately 12 hours apart. Ampyra may interact with other drugs. Tell your doctor all medications and supplements you use. During pregnancy, Ampyra should be used only if prescribed. It is unknown if Ampyra passes into breast milk. Consult your doctor before breastfeeding.

Our Ampyra (dalfampridine) Extended-Release Tablets Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

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 is Patient Information in Detail?

Easy-to-read and understand detailed drug information and pill images for the patient or caregiver from Cerner Multum.

Ampyra in Detail - Patient Information: Side Effects

Get emergency medical help if you have any of these 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 serious side effect such as:

  • seizure (convulsions);
  • pain or burning when you urinate;
  • problems with balance;
  • numbness, burning pain, or tingly feeling;
  • relapse or worsening of MS symptoms;

Less serious side effects may include:

  • headache, dizziness;
  • sleep problems (insomnia);
  • nausea, constipation, upset stomach;
  • weakness;
  • stuffy nose, sinus pain, sore throat; or
  • back pain.

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.

Read the entire detailed patient monograph for Ampyra (Dalfampridine Extended-Release Tablets)

What is Prescribing information?

The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.

Ampyra FDA Prescribing Information: Side Effects
(Adverse Reactions)


Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice.

The following adverse reactions are described in more detail in the WARNINGS AND PRECAUTIONS section of the label: Seizures, Anaphylaxis, and Urinary Tract Infections.

Controlled Clinical Trials Experience

In three placebo-controlled clinical trials of up to 14 weeks duration, 4% (15/400) of patients treated with AMPYRA 10 mg twice daily experienced one or more treatment emergent adverse events leading to discontinuation, compared to 2% (5/238) of placebo-treated patients. The treatment emergent adverse events leading to discontinuation of at least 2 patients treated with AMPYRA and that led to discontinuation more frequently compared to placebo were headache (AMPYRA 0.5%, placebo 0%), balance disorder (AMPYRA 0.5%; placebo 0%), dizziness (AMPYRA 0.5%, placebo 0%), and confusional state (AMPYRA 0.3%, placebo 0%).

Table 1 lists adverse reactions that occurred in ≥ 2% of patients treated with AMPYRA 10 mg twice daily, and more frequently than in placebo-treated patients, in controlled clinical trials.

Table 1: Adverse reactions with an incidence ≥ 2% of AMPYRA treated MS patients, and more frequent with AMPYRA compared to placebo in controlled clinical trials

Adverse Reaction Placebo
10 mg twice
Urinary tract infection 8% 12%
Insomnia 4% 9%
Dizziness 4% 7%
Headache 4% 7%
Nausea 3% 7%
Asthenia 4% 7%
Back pain 2% 5%
Balance disorder 1% 5%
Multiple sclerosis relapse 3% 4%
Paresthesia 3% 4%
Nasopharyngitis 2% 4%
Constipation 2% 3%
Dyspepsia 1% 2%
Pharyngolaryngeal pain 1% 2%

Other Adverse Reactions

AMPYRA has been evaluated in a total of 1,952 subjects, including 917 MS patients. A total of 741 patients have been treated with AMPYRA for over six months, 501 for over one year and 352 for over two years. The experience in open-label clinical trials is consistent with the safety profile observed in the placebo-controlled clinical trials. As in controlled clinical trials, a dose-dependent increase in the incidence of seizures has been observed in open-label clinical trials with AMPYRA in patients with MS as follows: AMPYRA 10 mg twice daily 0.41 per 100 person-years (95% confidence interval 0.13-0.96); dalfampridine 15 mg twice daily 1.7 per 100 person-years (95% confidence interval 0.21-6.28).

Read the entire FDA prescribing information for Ampyra (Dalfampridine Extended-Release Tablets)

Report Problems to the Food and Drug Administration


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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