Can steroids help reduce swelling caused by encephalitis?

Yes, sometimes. Encephalitis (brain swelling) may be mild to severe. Active medical management is required in both the diagnosis and treatment of the problem. Steroids are sometimes used, as they are a very useful at reducing inflammation. Though they are not used for all patients who present with encephalitis, they are part of many treatment regimens.
Yes. Antiviral medications such as Acyclovir or gancyclovir can be successful in treating herpes encephalitis, especially if started early in the illness. Anti-seizure medications and corticosteroids are added to the treatment regimen, if necessary.