Treatment of Bell's Palsy
Oral corticosteroids started within 72 hours of symptom onset are strongly recommended as first-line treatment for Bell's palsy, with prednisone 60-80mg daily for 7 days with taper showing significant improvement in recovery rates from 70% to 94%. 1
Diagnosis and Initial Assessment
Bell's palsy is characterized by acute onset of unilateral, lower motor neuron weakness of the facial nerve without an identifiable cause. Key diagnostic features include:
- Unilateral facial weakness affecting the forehead
- Absence of other neurologic abnormalities
- Rapid onset of symptoms
The House-Brackmann scale is recommended to quantify facial nerve function:
- Grade 1: Normal facial function
- Grade 2: Mild dysfunction (slight asymmetry)
- Grade 3: Moderate dysfunction (obvious but not disfiguring)
- Grade 4: Moderately severe dysfunction (obvious weakness/disfiguring)
- Grade 5: Severe dysfunction (barely perceptible movement)
- Grade 6: Total paralysis 1
Treatment Algorithm
First-Line Treatment
- Oral corticosteroids: Prednisone 60-80mg daily for 7 days with taper, started within 72 hours of symptom onset 1, 2
- This improves recovery rates from 70% to 94% 1
- For standard dosing: 50-60mg daily for 5 days followed by a 5-day taper 2
- Recent evidence suggests high-dose corticosteroids (≥80mg) may be more effective than standard-dose (40-60mg) with significantly decreased nonrecovery at 6 months (OR = 0.17,95% CI = 0.05-0.56) 3
Optional Additional Treatment
- Antiviral therapy: May be offered as an optional addition to steroid therapy
Eye Protection (Mandatory for Impaired Eye Closure)
- Artificial tears and lubricating ophthalmic drops/ointments
- Eye patching or taping
- Moisture chambers
- Sunglasses for daytime protection 1
Follow-Up and Referral Criteria
Refer patients to specialists if:
- New or worsening neurologic findings develop at any point (neurologist)
- Ocular symptoms occur (ophthalmologist)
- Incomplete facial recovery after 3 months (facial nerve specialist) 1
Special Considerations
Contraindications to Steroids
- Diabetes
- Morbid obesity
- Previous steroid intolerance 1
Rehabilitation Options
- Physical therapy may be beneficial for patients with more severe paralysis, though evidence is inconclusive 1, 2
- Psychological support for patients with persistent facial paresis/paralysis who may experience depression 1
Reconstructive Procedures
For patients with incomplete recovery, discuss potential reconstructive procedures with a facial plastic surgeon:
- Eyelid weights
- Brow lifts
- Static and dynamic facial slings 1
Evidence Quality and Caveats
The recommendation for corticosteroid therapy is based on high-quality evidence from multiple studies. A landmark study published in NEJM showed that at 9 months, recovery rates were 94.4% for prednisolone versus 81.6% for no prednisolone (P<0.001) 4.
The evidence for antiviral therapy is less robust. The same NEJM study found no significant benefit of acyclovir alone (85.4% recovery vs 90.8% for no acyclovir, adjusted P=0.10) or additional benefit when combined with prednisolone 4. However, some studies suggest a potential benefit of combination therapy with valacyclovir and prednisone, particularly in elderly patients 5.
The most recent evidence suggests high-dose corticosteroids may be more effective than standard doses, but this finding comes from studies with serious risk of bias and requires confirmation in larger, more robust trials 3.
Common Pitfalls
- Delaying corticosteroid treatment beyond 72 hours of symptom onset
- Using antiviral therapy alone without corticosteroids
- Failing to provide adequate eye protection for patients with impaired eye closure
- Not referring patients with incomplete recovery after 3 months