Comes on over a period of 12 – 36 hours. Prodromes can happen – facial numbness, altered taste, or pain around the ear. Initially progressive, but progression should have halted by 3/52 and if it continues to progress after that time think possible SOL. Recovery takes place over about 3 – 6 months.
The facial nerve carries taste fibres from the anterior two-thirds of the tongue and fibres to the tear glands, and controls the staepedius muscle. Symptoms can therefore include:
- Dry eye or excessive tearing
- Altered taste sensation
- Increased sensitivity to loud noise
- Ear pain
Check for other neurological signs, the presence of which excludes Bell’s palsy. Also check for shingles in the external auditory meatus and the mouth – Ramsay Hunt syndrome. If detected, discuss with ENT whether to treat with antivirals +/- steroids. Check BP and blood glucose – hypertension & diabetes can cause facial palsy.
Remember that sparing of the forehead suggests upper motor neurone lesion rather than Bell’s.
- Drops during the day
- Regularly close eyelid manually during the day
- Lacri-lube and eye pad at night
- Wear glasses
Refer to ophthalmology if concerns about eye care.
No clear evidence as to optimum steroid dose – most common recommendation is for 60 – 80 mg Prednisolone od for 7/7. Unclear whether it’s better to stop or do gradual reduction after that. There is in fact borderline evidence for antivirals from meta-analysis – aciclovir 400 mg 5 x daily for ten days or valaciclovir 1 g tds for one week. However, if renal function is poor these should be avoided as can precipitate decline in renal function.
Review at 3/52 to check starting to recover and 6/12 to check recovered.
- Atypical presentation/doubt over diagnosis
- Progressive after 3/52
- Not resolved at 6/12
- Occurs in pregnancy.
Options if doesn’t fully recover:
- Facial physio
- Tarsorraphy to improve eye closure if needed (gold weight placed in eyelid)
- Plastic surgery to improve appearance
(From BMJ learning module)