The last AAN guideline on Bell’s palsy is 11 years old and has just been updated. The reviewers found 3 newer studies of steroid treatment, which enrolled ~ 1000 subjects total. Prednisone (60 mg daily x 5 days then tapered for 5 days or 25 mg bid x 10 days) increased the probability of complete recovery by 13-15%; NNT 6-8. (That’s about the same effect size as tPA for acute stroke. I wonder how many docs would withhold prednisone in the “ideal” Bell’s palsy case?)
Anyway, we basically knew that. The antiviral data are more interesting. Three new studies of ~ 1500 subjects failed to show benefit. The studies lacked power to exclude a small benefit (risk difference < 7%) but for any difference higher than that, they found it “highly unlikely” that antivirals are effective.