BMJ  2005;330:1374 (11 June), doi:10.1136/bmj.330.7504.1374

Primary care

10-minute consultation

Bell's palsy

¹ Division of Medical Education, Warwick Medical School, University of Warwick, Coventry CV4 7AL Joanna.piercy{at}warwick.ac.uk

Introduction

A 32 year old man presents to you with sudden onset of weakness on the left side of his face. He also says that he is unable to close his left eye. He is otherwise well and last saw a doctor five years ago. He is anxious and thinks he has had a stroke.

What issues you should cover

Associated symptoms—Patients with Bell's palsy commonly feel pain in or behind the ear. Numbness can occur on the affected side of the face. Loss of taste on the ipsilateral anterior two thirds of the tongue is common. Ask about associated hyperacusis and any presence of rash that may indicate herpes zoster.

Aetiology—Ask about recent viral infection and recent immunisation. The causes of Bell's palsy are unknown, but the possibilities include viral infection, heredity, autoimmune or vascular ischaemia, of which the most likely cause is viral.

Incidence—Bell's palsy is commonest in the age group 10 to 40 years. Each year about 20 cases per 100 000 people occur.

What you should do

Examination

• You will need to differentiate between an upper and lower motor neurone lesion of the facial nerve. A lower motor neurone lesion occurs with Bell's palsy, whereas an upper motor neurone lesion is associated with a cerebrovascular accident. A lower motor neurone lesion causes weakness of all the muscles of facial expression. The angle of the mouth falls. Weakness of frontalis occurs, and eye closure is weak. With an upper motor neurone lesion frontalis is spared, normal furrowing of the brow is preserved, and eye closure and blinking are not affected.
  
• Check that no other cranial nerves are involved. Bell's palsy is seventh nerve palsy in isolation. Look also for a painful rash over the ear, which indicates Ramsay Hunt syndrome caused by herpes zoster virus.
  
• Look for pointers to a more serious underlying cause that might require urgent referral of the patient: bilateral Bell's palsy; recurrent Bell's palsy; association with a rash elsewhere or with feeling generally unwell (which may indicate sarcoid or Lyme disease); or a previous episode that could have been the effect of demyelination. Although it is rare, always bear in mind the possibility of a seventh nerve palsy caused by a space occupying lesion.
  

Information websites for patients Bell's Palsy Information Site (www.bellspalsy.ws). This site has information on causes, symptoms, treatment, and rehabilitation. It also has a good "frequently asked questions" page. Bell's Palsy Association (www.bellspalsy.org.uk). This is a UK based information site for patients.

Useful reading Bandolier. Bell's palsy systematic reviews. www.jr2.ox.ac.uk/bandolier/booth/neurol/Bellsyre.html Holland NJ, Weiner GM. Recent developments in Bell's palsy. BMJ 2004;329: 553-7[Free Full Text] Salinas R. Bell's palsy. In: Clinical evidence concise. Issue 11. London: BMJ Publishing, 2004: 311

Treatment

• Two recent systematic reviews concluded that Bell's palsy can be effectively treated with corticosteroids in the first seven days after onset, with a further 17% of patients having a good outcome in addition to the 80% that spontaneously improve. Recovery rates in patients treated within 72 hours were enhanced with the addition of aciclovir. It is thought that prednisolone acts by reducing oedema of the facial nerve. Antivirals inhibit viral replication. So, recent evidence supports the use of oral prednisolone and aciclovir in patients with moderate to severe palsy, ideally within 72 hours but up to seven days from onset of symptoms. Prednisolone should be prescribed at a dosage of 1 mg/kg/day (maximum 80 mg daily) for the first week, with the dosage tapering off over the second week. Aciclovir is given at a dosage of 800 mg five times a day for five days.
  
• As blinking is affected, and his eye may not close, consider an eye pad or taping of the lid so that he can sleep. His cornea will be dry, so prescribe artificial tears.
  
• Reassure him. Patients are often highly anxious and will need to be firmly reassured that this is not a cerebrovascular accident. Tell him that most patients get better but that a minority won't.
  

Follow up

• Two thirds of patients recover spontaneously, and 85% report some improvement in the first three weeks. In the other 15% of patients some improvement occurs by 3-6 months. Patients need follow up for assessment of recovery and support.
  
• Referral to an ear, nose, and throat specialist is advisable for all cases after treatment is begun. Patients with incomplete recovery of facial nerve function may ultimately need to be referred to an ophthalmologist for tarsorrhaphy.
  

---

This is part of a series of occasional articles on common problems in primary care

The series is edited by general practitioners Ann McPherson and Deborah Waller (ann.mcpherson{at}dphpc.ox.ac.uk)

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    StumbleUpon    Technorati    What's this?

Relevant Article

Recent developments in Bell's palsy

N Julian Holland and Graeme M Weiner
BMJ 2004 329: 553-557. [Extract] [Full Text] [PDF]

Rapid Responses:

Read all Rapid Responses

Bell'sPalsy

Chidambaran Ganapathy, et al.
bmj.com, 10 Jun 2005 [Full text]

HTA funded trial in progress for Bell’s Palsy in Scotland.

Frank M Sullivan, et al.
bmj.com, 11 Jun 2005 [Full text]

Rule out Lyme disease with spinal tap before giving steroids!

Mats G Reimer
bmj.com, 12 Jun 2005 [Full text]

Bell's Palsy : aetiology should include iatrogenic too

Dr. Arunachalam Kumar
bmj.com, 12 Jun 2005 [Full text]

Bell's Palsy

Peter G Procopis
bmj.com, 13 Jun 2005 [Full text]

Steroids Not Proven in Bell’s Palsy—The Legacy of Bad Science

Michael E Stuart, et al.
bmj.com, 13 Jun 2005 [Full text]

Acupuncture for Bell's palsy

John P Heptonstall
bmj.com, 14 Jun 2005 [Full text]

Bell's , pregnancy and diabetes

Adam P Morton
bmj.com, 15 Jun 2005 [Full text]

The importance of clinical examination in 'Bell's Palsy'

Gavin W Watters
bmj.com, 21 Jun 2005 [Full text]

Bell's palsy and aciclovir

Akram A. Hosseini, et al.
bmj.com, 22 Jun 2005 [Full text]

Don't leave out the eyes and ears in facial palsy

Dipan N Mistry, et al.
bmj.com, 27 Jun 2005 [Full text]

Bell's Palsy: A diagnosis of exclusion

James W Moor, et al.
bmj.com, 27 Jun 2005 [Full text]

Bell's Palsy: Propagating Poor Quality Evidence

Claire Hopkins
bmj.com, 7 Jul 2005 [Full text]

Online poll

Find out more >>