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Prescribe prednisolone alone for Bell’s palsy diagnosed within 72 hours of symptom onset

BMJ 2009; 338 doi: (Published 06 February 2009) Cite this as: BMJ 2009;338:b255
  1. Vishnu Madhok, clinical research fellow1,
  2. Gavin Falk, clinical research fellow2,
  3. Tom Fahey, professor of primary care medicine2,
  4. Frank M Sullivan, director of Scottish School of Primary Care1
  1. 1Tayside Centre for General Practice, Division of Community Health Sciences, University of Dundee, Dundee DD2 4BF
  2. 2Department of General Practice, Royal College of Surgeons in Ireland, 120 St Stephen’s Green, Dublin 2, Ireland
  1. Correspondence to: F M Sullivan f.m.sullivan{at}
  • Accepted 13 August 2008

The authors explain their reasons for the need for a new change in treatment for early Bell’s palsy

The clinical problem

Bell’s palsy affects 11 to 40 people per 100 000 population each year,1 and although most patients recover, as many as 30% are left with facial disfigurement and pain. Uncertainty surrounds the most commonly used treatments, corticosteroids and antiviral agents: two Cochrane reviews examining their effectiveness concluded that there were unsatisfactory data to determine definitive treatment.2 3 However, on the basis of a more recent randomised controlled trial of prednisolone and aciclovir for early Bell’s palsy,4 we now propose that prednisolone should be prescribed immediately on diagnosis and that aciclovir either alone or in combination does not confer any benefit.

The evidence for change

The treatment of Bell’s palsy has been an area of clinical uncertainty in terms of whether to treat with corticosteroid or antiviral therapy. Two separate Cochrane reviews in 2004 examined the effectiveness of corticosteroids and antiviral agents in patients with Bell’s palsy.2 3 The first Cochrane review included three randomised controlled trials with 117 patients, and the second review included two randomised control trials with 200 patients.2 3 Each review concluded that the data were unsatisfactory for determining definitive treatment. Following these two reviews, England’s National Institute for Health Research commissioned a randomised controlled trial within primary care to look at the effectiveness of prednisolone and aciclovir in treating early Bell’s palsy.4 This trial included twice as many patients as did the Cochrane reviews, thereby reducing the selection bias found in hospital based studies.

In this newly commissioned trial, over a two year period 752 patients with symptoms suggestive of Bell’s palsy were referred from primary care to 17 hospital based receiving centres in Scotland to be assessed within 72 hours of symptom onset. Altogether, 551 patients met the inclusion criteria and were randomised twice, resulting in four study groups. Each group received a combination of two preparations: prednisolone plus placebo; aciclovir plus placebo; prednisolone plus aciclovir; or two placebo capsules. Facial nerve function was the primary outcome and was assessed using the House-Brackmann scale, with quality of life, appearance, and pain as secondary outcomes (table).

Full recovery from Bell’s palsy at three and nine months. Adapted from Sullivan et al4

View this table:

Prednisolone provides an effective treatment for Bell’s palsy—the number needed to treat (NNT) for one additional person to experience full facial function being six and eight at three and nine months respectively.

Barriers to change

Effective dissemination of this new knowledge on how the best to treat Bell’s palsy is needed. This article and others in review publications such as the Drug and Therapeutics Bulletin (, together with the incorporation of the new findings into the online resource Map of Medicine (, will enable these findings to be more widely known. This will make it more likely that patients receive corticosteroids within three days of the onset of symptoms.

How should we change our practice?

Prednisolone should be prescribed as first line treatment in patients diagnosed with Bell’s palsy within 72 hours of onset. Corticosteroids alone are easy for patients to take, are well tolerated, and now have clear supporting evidence. They are also more cost effective, with the daily dose of 50 mg (25 mg twice daily) of prednisolone costing £0.52 compared with £0.70 for 2 g (400 mg five times daily) of aciclovir; patients are recommended to take a 10 day course. Corticosteroids are contraindicated in patients with systemic infection. It remains to be seen if other antiviral agents, such as valaciclovir, have any benefit in the treatment of Bell’s palsy in primary care.


We searched Medline and the Cochrane Library to identify published randomised controlled trials and systematic reviews that assessed the efficacy of steroids and antivirals in the treatment of Bell’s palsy. We also consulted widely among specialists and generalists, as well as drug companies, to identify relevant published evidence. A single recent study dominates the current evidence base as the largest randomised control trial providing the best supportive evidence on management of the early stages for patients presenting in primary care

Key points

  • Prednisolone given within 72 hours of onset of Bell’s palsy increases the chance of complete recovery at three and nine months

  • Combining the antiviral aciclovir with prednisolone confers no additional benefit

  • Prednisolone is easy to take, well tolerated, and cheap


Cite this as: BMJ 2009;338:b255


  • Change Page aims to alert clinicians to the immediate need for a change in practice to make it consistent with current evidence. The change must be implementable and must offer therapeutic or diagnostic advantage for a reasonably common clinical problem. Compelling and robust evidence must underpin the proposal for change.

  • Contributors: TF and FMS had the original idea for article; GF and VM did the literature research; all authors contributed to writing the article; and FMS is the guarantor.

  • Competing interests: FMS has received grant support from GlaxoSmithKline for projects unrelated to the New England Journal of Medicine trial on which the suggested changes are based.

  • Provenance and peer review: Not commissioned; externally peer reviewed.


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