Steroids and antivirals are the two major types of pharmacological treatments that have been used to improve outcomes from Bell’s palsy. The presumed pathophysiology of Bell’s palsy, namely inflammation and viral infection, provide the rational for these treatments.

During decompression surgery, surgeons have noted facial nerve swelling for decades. Inflammation has been suggested to be partly responsible for the associated paralysis due to recent enhancement of the facial nerve on magnetic resonance imaging that has been observed in Bell’s palsy. As a result, Bell’s palsy has been treated with steroids, which has shown to significantly improve the outcomes when compared with placebo.

The neuronal inflammation that is associated with Bell’s palsy is thought to be secondary to viral infection. In patients with Bell’s palsy, the herpes simplex virus has been detected in the endoneurial fluid. Some clinicians treat patients with antivirals including valaciclovir, aciclovir, and famciclovir on the basis of this evidence. The role of combination therapy with steroids plus antivirals has been investigated for the treatment of Bell’s palsy, but the exact benefits of antivirals alone aren’t clear yet.

However, somewhat conflicting results were produced by studies, and there is still debate over the effectiveness of antivirals on top of steroids. Aciclovir combined with prednisone has been suggested to be “possibly effective” by the most recent guidelines from the American Academy of Neurology. Many clinicians treat Bell’s palsy with combination therapy in spite of the lack of clear evidence.

To determine whether steroid treatment plus antivirals provides a better degree of facial muscle recovery than do steroids alone, a meta-analysis has been performed, given the emergence of this clinical practice and the conflicting data on the benefits of antivirals over and above those of steroids.There were 6 trials, with a total of 1145 patients.

• 571 patients received steroids and antivirals
• 574 patients received steroids alone

Compared with steroids alone, the pooled odds ratio for facial muscle recovery showed no benefit of steroids plus antivirals. This meta-analysis doesn’t support the routine addition of antivirals to steroids in Bell’s palsy because when compared with steroids alone, adding antivirals to steroids hasn’t provided an added benefit in achieving at least partial facial muscle recovery.

However, in patients with severe facial muscle paralysis at presentation who don’t have Varicella zoster virus reactivation, the benefit of antiviral therapy combined with steroids is still not clear. To resolve this issue, future prospective double blind studies are needed that use modern diagnostics for the detection of Herpes virus reactivation, such as polymerase chain reaction. However, on the basis of the improved bioavailability of newer antivirals over aciclovir, these future trials should study newer antivirals such as famciclovir or valaciclovir.

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Prepared By: Dr. Mehyar Al-Khashroum
Edited By: Miss  Araz Kahvedjian