Two Cases of Acyclovir Neurotoxicity in End Stage of Renal Disease

Acyclovir is an anti-viral nucleoside analogue that was discovered in 1972. Since it was put to use in clinical practice, some adverse events had been reported. Renal dysfunction and disturbance of central nervous system are the two major adverse effects. A 60-year-old man who was being treated with peritoneal dialysis was admitted for sudden onset of sensory-neural hearing loss. A 67-year-old man who was being treated with hemodialysis was also admitted for Bell's palsy. After two days of treatment with intravenous acyclovir and oral prednisolone, they had hallucinations, myoclonus, disoriented mentality and agitation. Furthermore, the latter had stupor. We did some laboratory examination, brain MRI and electroencephalography (EEG), but there was no cause for neurologic abnormality. In the clinical suspicion of acyclovir neurotoxicity, we discontinued acyclovir and went on dialysis therapy. They fully recovered after several days. Our cases further reinforces the claim that the dose of acyclovir should be reduced in patients with renal failure and dialysis is a good form of treatment for overdosage.