Other names: Fampyra (Europe), Ampyra (US)

Fampridine is a drug that has been shown to improve walking speed for some adults with multiple sclerosis. It was licensed in 2011 but is rarely available on the NHS.

How is fampridine given?

Fampridine is taken orally as tablets. Most people are prescribed one tablet in the morning and one at night. Fampridine is formulated as a prolonged-release tablet which means that the drug is released slowly to give a more steady supply of fampridine in the body.

Side effects and contraindications

Urinary tract (bladder) infections are very common. Other common side effects include dizziness, headache, back pain, difficulty sleeping, feeling sick and stomach upsets.

Being prescribed fampridine

Fampridine is only available on prescription under the supervision of a doctor with knowledge of MS. The doctor usually provides an initial prescription for two to four weeks and then the treatment is assessed to see if it is working, usually by timing how long it takes to walk a short distance (eg. 25 feet).

Up to a third of people find that fampridine improves their mobility, so only this group would be prescribed fampridine in the longer term. The initial two to four week trial is currently funded by the manufacturer.

Licensing and availability

Fampridine was granted a conditional marketing authorisation by the European Medicines Agency (EMA) in July 2011. The licence requires the manufacturer, Biogen Idec, to carry out further research into the benefits and long-term safety of fampridine. The EMA reviews new information on this medicine at least every year. A conditional marketing authorisation is granted when a medicinal product is considered to fulfil an unmet medical need and should be made available despite the fact that further data are still required.

In 2014, the NICE MS Clinical Guideline 186 concluded that fampridine was not a cost effective treatment for lack of mobility in MS. Consequently, it is not recommended for use on the NHS in England and Wales.

In Scotland, fampridine is not recommended for use within the NHS as the Scottish Medicines Consortium (SMC) has not received a submission from the manufacturers of fampridine.

Some people with MS opt to pay privately for fampridine. The cost is around £4,700 per year (at October 2014).

How fampridine works

Fampridine is a formulation of 4-aminopyridine, a potassium channel blocker. It works by stopping potassium leaving nerve cells which have been damaged by MS so letting signals pass down the nerve more normally. Consequently, some people are able to walk better.

For reasons that are not understood, some people respond well to fampridine and experience improved mobility, but others do not.

Fampridine research

There have been a number of clinical trials of fampridine. For example, a phase III study involving 301 people with relapsing or progressive MS who were treated for 14 weeks, showed a greater proportion of people taking fampridine had a consistent improvement in walking speed compared to people taking placebo (35% v 8%). This improvement was maintained for the duration of the study.

A review of a wide range of clinical trials by NICE, completed as part of the development of the 2014 MS Clinical Guideline, concluded that fampridine had a positive effect on walking speed compared with placebo. However, there was little good evidence for an appreciable effect on EDSS, a commonly used measure of disability.


  • Goodman AD, et al. Dose comparison trial of sustained-release fampridine in multiple sclerosis. Neurology 2008;71(15):1134-1141. Summary
  • Goodman AD, et al. Sustained-release oral fampridine in multiple sclerosis: a randomised, double-blind, controlled trial. Lancet 2009;373(9665):732-738. Summary
  • Rabadi MH, et al. Sustained-release fampridine (4-aminopyridine) in multiple sclerosis: efficacy and impact on motor function. Drugs in R&D 2013;13(3):175-181. Summary

Last updated: 8 October 2014
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