ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005


The Latest on X

Kidney Week

Please note that you are viewing an archived section from 2023 and some content may be unavailable. To unlock all content for 2023, please visit the archives.

Abstract: TH-PO345

Valacyclovir Neurotoxicity: A Case Comparison of Peritoneal Dialysis and Hemodialysis

Session Information

  • Home Dialysis - I
    November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
    Abstract Time: 10:00 AM - 12:00 PM

Category: Dialysis

  • 802 Dialysis: Home Dialysis and Peritoneal Dialysis


  • Walker, Briahni Michele, UC Davis Health, Sacramento, California, United States
  • Ahamed, Alaa'i Ezzeldin, UC Davis Health, Sacramento, California, United States
  • Dhatt, Keerat, UC Davis Health, Sacramento, California, United States
  • Dao, Tram, UC Davis Health, Sacramento, California, United States
  • Young, Brian Y., UC Davis Health, Sacramento, California, United States

The standard treatment for acyclovir neurotoxicity in ESRD is hemodialysis (HD) as it eliminates roughly one-third of acyclovir per session. However, there are various reports of success with peritoneal dialysis (PD) intensification. We report an ESRD patient with acyclovir neurotoxicity given both PD and, after persistent symptoms, HD. This offers the unique opportunity to compare therapeutic effects.

Case Description

An 87-year-old man with ESRD on PD was hospitalized with confusion, ataxia, and visual hallucinations. Prior to admit, the patient had shingles and got valacyclovir 1gm q8 hours (ESRD max recommended dose = 500mg q24-48 hours). Neurologic symptoms began after his 3rd dose. He was adherent to home PD. Total KT/V 1 month prior was 2.09 with little residual GFR (KT/Vr = 0.06).
On admit, he was afebrile with left flank vesicular rash, slurred speech, slow motor skills, and imbalance. BMP had BUN 60 mg/dl, creatinine 11.7 mg/dl. CBC, cultures, toxicology, and CT head were negative. Acyclovir neurotoxicity was diagnosed.
Dialysis was performed and acyclovir levels were drawn (Figure). Patient declined initial recommendation of temporary HD. Yet, after no clinical change with 12 hours intense PD, he had HD, improving after each HD, and eventual neurotoxic resolution.


Valacyclovir, a prodrug of acyclovir, is efficacious in treating herpes zoster. We have a unique neurotoxic acyclovir overdose treated with PD and HD sequentially. Despite 12 hours of intervening PD, our patient’s acyclovir level took ~18 hours to reduce in half. In normal renal function, the elimination half-life of acyclovir is ~3 hours, yet in ESRD this increases to ~14 hours. Based on ESRD half-life, this suggests intense PD was not effective for acyclovir toxicity. In contrast, the acyclovir level dropped rapidly with each HD along with clinical improvement. In our patient, HD was the superior modality and should be considered first to avoid potential long-term neurotoxic injury in patients with minimal residual kidney function.