In addition, there is a small risk of neurologic disease and encephalitis, particularly in individuals with compromised immune systems and very young children.
The original use was against normally fatal or debilitating illness such as adult encephalitis, keratitis, in immunocompromised (transplant) patients, or disseminated herpes zoster.
Although parkinsonism was occasionally seen during the acute encephalitic phase of encephalitis lethargica, it was often encountered in the post-encephalitic phase.
