Intervention Review

Antiviral treatment for Bell's palsy (idiopathic facial paralysis)

  1. Ildiko Gagyor1,*,
  2. Vishnu B Madhok2,
  3. Fergus Daly3,
  4. Dhruvashree Somasundara2,
  5. Michael Sullivan4,
  6. Fiona Gammie2,
  7. Frank Sullivan5

Editorial Group: Cochrane Neuromuscular Disease Group

Published Online: 1 JUL 2015

Assessed as up-to-date: 7 OCT 2014

DOI: 10.1002/14651858.CD001869.pub6

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 7. Art. No.: CD001869. DOI: 10.1002/14651858.CD001869.pub6.

Author Information

  1. 1

    University of Göttingen, Department of General Practice/Family Medicine, Göttingen, Lower Saxony, Germany

  2. 2

    University of Dundee, Centre for Primary Care and Population Research, Division of Clinical and Population Sciences and Education, Dundee, Tayside, Scotland, UK

  3. 3

    Frontier Science (Scotland) Ltd, Kingussie, Inverness-shire, UK

  4. 4

    University of Edinburgh, School of Clinical Sciences, Edinburgh, Lothian, UK

  5. 5

    North York General Hospital, University of Toronto, Department of Family and Community Medicine, Toronto, ON, Canada

*Ildiko Gagyor, Department of General Practice/Family Medicine, University of Göttingen, Humboldtalle 38, Göttingen, Lower Saxony, 37073, Germany.

Publication History

  1. Publication Status: Edited (conclusions changed)
  2. Published Online: 1 JUL 2015




  1. Top of page
  2. Abstract
  3. Plain language summary
  4. Laički sažetak


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.

Search methods

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contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data.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.

Selection criteria

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.

Main results

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.

Incomplete recovery

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 of 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 events

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.

Authors' conclusions

Moderate-quality evidence from randomised controlled trials showed no additional benefit from the combination of antivirals with corticosteroids compared to corticosteroids alone for the treatment of Bell's palsy of various degrees of severity. Moderate-quality evidence showed a small but just significant benefit of combination therapy compared with corticosteroids alone in severe Bell’s palsy. Corticosteroids alone were more effective than antivirals alone and antivirals plus corticosteroids were more effective than placebo or no treatment. There was no benefit from antivirals alone over placebo.

Moderate-quality evidence indicated that the combination of antivirals and corticosteroids reduced sequelae of Bell's palsy compared with corticosteroids alone.

We found no significant increase in adverse events from the use of antivirals compared with either placebo or corticosteroids, based on moderate-quality evidence.


Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. Laički sažetak

Antiviral treatment for Bell's palsy

Review question

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.

Study characteristics

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 corticosteroids; antivirals alone to placebo or no treatment; antivirals alone to corticosteroid treatment alone; and antiviral treatment in combination with corticosteroids to placebo or no treatment. The duration of the included studies ranged from three months to 12 months.

Key results and quality of the evidence

Incomplete recovery

According to moderate-quality evidence, combining antivirals with corticosteroids did not improve rates of incomplete recovery from Bell's palsy compared to corticosteroids alone. This finding was based on data from nine trials involving 1715 people with Bell's palsy of various degrees of severity.

We were able to use data from four of the studies (478 participants) to examine treatment effects in severe Bell's palsy (that is people who have complete or almost-complete facial paralysis). The results showed that in this group, the addition of antiviral treatment to corticosteroids probably improved rates of incomplete recovery over corticosteroid treatment alone.

In other analyses, we found the following:

- corticosteroids alone were more effective than antivirals alone in terms of incomplete recovery (1169 participants);

- antivirals plus corticosteroids were more effective than placebo or no treatment (658 participants); and

- antivirals alone were less effective than placebo (although this difference was not significant) (658 participants).

Long-term after-effects of Bell's palsy

Three trials (869 participants) assessed the long-term after-effects of Bell's palsy, such as excessive tear production and synkinesis (involuntary movement of muscles occurring at the same time as deliberate movement). The combination of antivirals and corticosteroids reduced long-term after-effects of Bell's palsy compared with corticosteroids alone. The evidence was of moderate quality.

There were fewer long-term after-effects of Bell's palsy after treatment with corticosteroids alone than with antivirals alone (three trials, 873 participants).

Adverse events

Based on the evidence from three trials (877 participants), none of the 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.


Laički sažetak

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. Laički sažetak

Antivirusni lijekovi za Bellovu paralizu

Istraživačko pitanje

U ovom Cochrane sustavnom pregledu analizirani su dokazi o učinku same antivirusne terapije ili u kombinaciji s bilo kojom drugom terapijom na Bellovu paralizu.

Dosadašnje spoznaje

Bellova paraliza je bolest živca koji se nalazi na licu (facijalnog živca), a koja uzrokuje paralizu jedne strane lica. Neke su studije pokazale da je uzrokovana istim virusnim infekcijama koje uzrokuju herpesne promjene na licu (Herpes simplex) ili herpes zoster (varicella zoster). Ako je to točno, antivirusni lijekovi će vjerojatno pomoći oporavku. Paraliza je obično privremena, čak i kada se ne liječi, iako bez terapije u 20% osoba ostavlja trajna unakaženja lica ili bol. Drugi Cochrane pregled je već potvrdio učinkovitost kortikosteroida kod Bellove paralize.

Značajke istraživanja

Pronađeno je 11 kontroliranih studija koje su uključile 2883 sudionika s blagom, umjerenom ili teškom jednostranom Bellovom paralizom nepoznatog uzroka. Sudionici su bili u dobi od 14 do 84 godine. Studije su usporedila antivirusne lijekove u kombinaciji s kortikosteroidima sa samim kortikosteroidima; same antivirusne lijekove u usporedbi s placebom ili nikakvim liječenjem; same antivirusne lijekove u usporedbi sa samim kortikosteroidima te antivirusnu terapiju u kombinaciji s kortikosteroidima s placebom ili nikakvom terapijom. Trajanje uključenih studija bilo je od tri mjeseca do 12 mjeseci.

Ključni rezultati i kvaliteta dokaza

Djelomični oporavak

Prema dokazima umjerene kvalitete, kombiniranjem antivirusnih lijekova s kortikosteroidima nije povećalo učestalost djelomičnog oporavka od Bellove paralize u usporedbi sa samim kortikosteroidima. Ti se rezultati temelje na podatcima iz 9 studija u koje je bilo uključeno 1715 ljudi s Belovom paralizom različite težine.

Autori su iskoristili podatke iz 4 studije (478 ispitanika) kako bi se ispitivali učinci liječenja na tešku Bellovu paralizu (osobe koje imaju potpunu ili gotovo potpunu paralizu lica). Rezultati su za ovu grupu pokazali da dodavanje antivirusne terapije kortikosteroidima vjerojatno poboljšava stope djelomičnog oporavka u usporedbi sa samim kortikosteroidima.

U drugim analizama utvrđeno je sljedeće:

- sami kortikosteroidi bili su djelotvorniji nego sami antivirusni lijekovi za postizanje djelomičnog oporavka (1169 ispitanika);

- kombinacija antivirusnih lijekova i kortikosteroida bila je djelotvornija nego placebo ili nikakva terapija (658 ispitanika); i

- sami antivirusni lijekovi bili su manje djelotvorni nego placebo (iako ta razlika nije bila značajna) (658 ispitanika).

Dugoročne posljedice Bellove paralize

Tri studije (869 ispitanika) procijenile su učinak terapije na dugoročne posljedice Bellove paralize kao što su pretjerano stvaranje suza i sinkineza (nevoljni pokreti mišića koji se javljaju u isto vrijeme kad i namjerni pokreti). Kombinacija antivirusnih lijekova i kortikosteroida smanjila je učestalost dugoročnih posljedica Bellove paralize u usporedbi sa samim kortikosteroidima. Dokazi su bili umjerene kvalitete.

Također je bilo manje dugoročnih posljedica Bellove paralize nakon davanja samih kortikosteroida nego samo s antivirusnim lijekovima (tri ispitivanja, 873 ispitanika).


Na temelju dokaza iz tri ispitivanja (877 ispitanika), nijedna od terapija nije pokazala značajne razlike u nuspojavama, pri čemu treba uzeti u obzir umjerenu kvalitetu podataka.

Dokazi u ovom sustavnom pregledu odnose se na studije objavljene do listopada 2014. godine.

Bilješke prijevoda

Hrvatski Cochrane
Prevela: Božena Armanda
Ovaj sažetak preveden je u okviru volonterskog projekta prevođenja Cochrane sažetaka. Uključite se u projekt i pomozite nam u prevođenju brojnih preostalih Cochrane sažetaka koji su još uvijek dostupni samo na engleskom jeziku. Kontakt: