Acyclovir-induced neurotoxicity in an elderly patient: Report of a case

Abstract

Acyclovir (ACV) is well known as an effective treatment for herpes zoster (VZV). ACV is generally considered safe, and neurotoxicity rarely appears as a side-effect. We report a case of an 86-year-old man of ACV neurotoxicity without history of renal failure. Six days before admission, he visited a dermatologist for left cheek inflammation. He was prescribed ACV at a dose of 3200mg daily for the treatment of VZV. After 3 days, he developed diarrhea and loss of appetite, and was diagnosed with dehydration. He was admitted to our hospital with impaired consciousness without focal neurologic deficit and renal dysfunction. ACV neurotoxicity and acute renal failure was considered and ACV administration was discontinued. Neurological and renal symptoms immediately recovered.
Although ACV-induced neurotoxicity is seen more commonly in patients on hemodialysis or with severe renal dysfunction, this condition has also been reported in elderly patients without abnormalities in renal function. ACV is mainly excreted by the kidneys, therefore, it is possible that ACV neurotoxicity in elderly patients could be caused by dehydration or the combination of other renally excreted drugs.