Aims. To alert practitioners to the danger of acyclovir neurotoxicity
occurring in the presence of renal failure. Methods. Two case reports
of acyclovir neurotoxicity in the patients on continuous ambulatory pe
riteneal dialysis. Results. In one case neurotoxicity resulted from th
e use of a dosage regimen that would be appropriate in patients with n
ormal renal function. In the other case, neurotoxicity occurred even t
hough a reduced dose of acyclovir was given. Supportive management res
ulted in a complete recovery. Conclusions. In patients with end stage
renal failure with varicella tester infections, when acyclovir is pres
cribed the loading dose should be 400 mg and the maintenance dose shou
ld be 200 mg twice daily.