Neurological complications of varicella zoster virus (VZV) reactivation have rarely been described in dialysis patients. We report a case of a continuous ambulatory peritoneal dialysis (CAPD) patient who developed herpes zoster encephalitis. The patient was treated with acyclovir and steroids and had a slow but complete return to her prior cognitive status. The available literature is reviewed and the differential diagnosis with acyclovir toxicity is discussed.