Antiviral treatment for Bell's palsy (idiopathic facial paralysis)
Editorial Group: Cochrane Neuromuscular Disease Group
Published Online: 4 MAY 2015
Assessed as up-to-date: 7 OCT 2014
Copyright © 2015 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Gagyor I, Madhok VB, Daly F, Somasundara D, Sullivan M, Gammie F, Sullivan F. Antiviral treatment for Bell's palsy (idiopathic facial paralysis). Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD001869. DOI: 10.1002/14651858.CD001869.pub5.
- Publication Status: New search for studies and content updated (no change to conclusions)
- Published Online: 4 MAY 2015
Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell’s palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy.
To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell’s palsy.
On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies.
We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains.
Data collection and analysis
Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures.
Eleven trials, including 2883 participants, met the inclusion criteria and are included in the final analysis. We added four studies to the previous review for this update. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding.
We found no significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell’s palsy (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.47 to 1.02, n = 1715). For people with severe Bell’s palsy (House-Brackmann scores of 5 and 6 or the equivalent in other scales), we found a reduction in the rate of incomplete recovery at month six when antivirals plus corticosteroids were used (RR 0.64, 95% CI 0.41 to 0.99, n = 478). The outcome for the participants receiving corticosteroids alone was significantly better than for those receiving antivirals alone (RR 2.09, 95% CI 1.36 to 3.20, n = 1169). The treatment effect of placebo was significantly lower than that of antivirals plus corticosteroids (RR 0.56, 95% CI 0.41 to 0.76, n = 658). Antivirals alone had a non-significant detrimental effect on the outcome compared with placebo (RR 1.10, 95% CI 0.87 to 1.40, n = 658).
Motor synkinesis or crocodile tears
In three trials comparing antivirals and corticosteroids with corticosteroids and placebo that assessed this outcome, we found a significant difference in long-term sequelae in favour or antivirals plus corticosteroids (RR 0.73, 95% CI 0.54 to 0.99, n = 869). Three trials comparing antivirals alone with corticosteroids alone investigating this outcome showed fewer sequelae with corticosteroids (RR 1.44, 95% CI 1.11 to 1.85, n = 873). We found no data on long-term sequelae for other comparisons.
Adverse event data were available in three studies giving comparison data on 1528 participants. None of the four comparisons (antivirals plus corticosteroids versus corticosteroids plus placebo or no treatment; antivirals versus corticosteroids; antivirals plus corticosteroids versus placebo; antivirals versus placebo) showed significant differences in adverse events between treatment and control arms. We could find no correlation with specific treatment within these results.
Moderate-quality evidence from randomised controlled trials showed no additional benefit from the combination of antivirals with corticosteroids compared to corticosteroids alone or with placebo, and no benefit from antivirals alone compared to placebo, for the treatment of Bell's palsy. Moderate-quality evidence showed a small but just significant benefit of combination therapy compared with corticosteroids alone in severe Bell’s palsy. We found no significant increase in adverse events from the use of antivirals compared with either placebo or corticosteroids.
Plain language summary
Antiviral treatment for Bell's palsy
We reviewed the evidence about the effect of antiviral therapy alone or in combination with any other therapy, on Bell's palsy.
Bell's palsy is a disease of the facial nerve that causes one side of the face to be paralysed. Some studies have suggested that it is caused by the same viral infections that cause cold sores (herpes simplex) or shingles (varicella zoster). If this is correct, antiviral drugs would be likely to help recovery. The paralysis is usually temporary even when left untreated, although without treatment about one person in five is left with permanent facial disfigurement or pain. A Cochrane review has already confirmed the effectiveness of corticosteroids in Bell’s palsy.
We identified 11 trials, which included 2883 participants with mild, moderate, or severe one-sided Bell’s palsy of unknown cause. Participants were aged from 14 to 84 years. The trials compared antivirals in combination with corticosteroids to corticosteroid treatment alone or in combination with placebo; antiviral treatment alone or in combination with placebo to placebo or no treatment only; antiviral treatment alone or in combination with placebo to corticosteroid treatment alone or in combination with placebo; and antiviral treatment in combination with corticosteroids to placebo or no treatment only. The duration of the included studies ranged from three months to 12 months.
Key results and quality of the evidence
This updated review provides moderate-quality evidence for no benefit for people with Bell's palsy from the combination of antivirals with corticosteroids compared to corticosteroids alone or with placebo, based on data from 1715 trial participants.
The combination of corticosteroids with antivirals is probably more effective than corticosteroids alone in the treatment of people with severe Bell’s palsy.
Antivirals alone (or combined with placebo) were not as effective as corticosteroids alone or corticosteroids in combination with antivirals.
Moderate-quality evidence showed a significant benefit with antivirals plus corticosteroids compared with corticosteroids alone in people with severe Bell’s palsy.
In three trials considerably more long-term after-effects of Bell's palsy were seen in people treated with corticosteroids alone than in people treated with antivirals and corticosteroids combined (moderate-quality evidence). There were also fewer long-term after-effects with corticosteroids alone than with antivirals alone (three trials).
Based on the evidence from three trials, none of the different treatments showed significant differences in adverse events, taking into account the moderate quality of data for this outcome.
The evidence in this review is current to October 2014.