What are the symptoms and treatment options for Bell's palsy?

Bell's Palsy Symptoms and Treatment

Bell's palsy is characterized by acute unilateral facial nerve paresis or paralysis with onset in less than 72 hours without an identifiable cause, involving the forehead and causing significant temporary oral incompetence and inability to close the eyelid. 1

Key Symptoms

• Facial Weakness/Paralysis

  • Unilateral facial weakness or paralysis involving the forehead (distinguishing it from central causes of facial weakness) 1, 2
  • Develops rapidly over 24-72 hours 1
  • May affect ability to raise eyebrows, close eyes tightly, smile, and puff out cheeks 1

• Associated Symptoms

  • Ipsilateral pain around the ear or face 1
  • Hyperacusis (increased sensitivity to sound) 1
  • Taste disturbance on anterior two-thirds of the tongue 1
  • Dry eye and mouth due to autonomic fiber involvement 1
  • Drooling or difficulty with oral competence 3

Diagnosis

• Diagnosis requires careful elimination of other causes through thorough history and physical examination 1

• Routine laboratory testing and diagnostic imaging are NOT recommended for initial diagnosis 1

• Features requiring further investigation include:

  • Second paralysis on same side
  • Isolated branch paralysis
  • Other cranial nerve involvement
  • No recovery after 3 months 1

• House-Brackmann Grading System is commonly used to assess severity (grades 1-6) 1

Treatment Algorithm

First-Line Treatment (within 72 hours of symptom onset)

1. Oral corticosteroids (for patients 16 years and older):

   • Prednisolone 50 mg daily for 10 days OR
   • Prednisone 60 mg daily for 5 days followed by a 5-day taper 1, 2
   • Strong evidence supports this: 83% recovery at 3 months with prednisolone vs 63.6% with placebo 1

2. Consider combination therapy:

   • May offer oral antiviral therapy in addition to oral steroids within 72 hours of symptom onset 1
   • Options include valacyclovir (1 g three times daily for 7 days) or acyclovir (400 mg five times daily for 10 days) 2
   • Note: Antiviral therapy alone should NOT be prescribed 1, 2

Eye Protection (Critical)

• Implement eye protection for all patients with impaired eye closure to prevent corneal damage 1
• Methods include:
  • Frequent lubricating ophthalmic drops throughout the day 1
  • Ophthalmic ointments (especially at night) 1
  • Moisture chambers using polyethylene covers for nighttime 1
  • Eye patching/taping (with careful instruction on proper technique) 1
  • Sunglasses for outdoor protection 1

Special Populations

• Children: Better prognosis with higher spontaneous recovery rates (up to 90%); evidence for steroid use less conclusive 1, 2
• Pregnant women: Treatment should be individualized with careful assessment of benefits and risks 1

Follow-up and Referral

• Reassess or refer to specialist if:

  • New or worsening neurologic findings at any point
  • Ocular symptoms develop
  • Incomplete facial recovery 3 months after symptom onset 1

• MRI with and without contrast is the imaging test of choice when indicated (atypical presentations, no recovery after 3 months) 1

Prognosis

• Overall prognosis is good 2
• Approximately 70% of patients with complete paralysis recover facial function completely within 6 months 1
• Patients with incomplete paralysis have higher recovery rates (up to 94%) 1
• Most patients begin showing signs of recovery within 2-3 weeks 1
• Complete recovery typically occurs within 3-4 months for most patients 1

Potential Complications

• Short-term: Incomplete eyelid closure with resultant dry eye 4
• Long-term: Approximately 30% of patients may experience permanent facial weakness with muscle contractures 1, 4
• Synkinesis (involuntary co-contraction of certain facial muscles due to misdirected regrowth of facial nerve fibers) 2

Common Pitfalls to Avoid

• Delaying treatment beyond 72 hours, which reduces effectiveness of therapy 1
• Using antiviral therapy alone, which is ineffective 1, 2
• Failing to test forehead function, which is critical to distinguish Bell's palsy from central causes of facial weakness 1
• Inadequate eye protection, which can lead to corneal damage 1
• Missing subtle weakness or inadequate eye assessment 1