Peer-reviewed veterinary case report
Unexpected side effects during and after GS-441524 treatment for cats
By Buchta, Katharina et al.·Published in Viruses·2025·LMU Small Animal Clinic, Germany·View original on PubMed →
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Original publication title: Unexpected Clinical and Laboratory Observations During and After 42-Day Versus 84-Day Treatment with Oral GS-441524 in Cats with Feline Infectious Peritonitis with Effusion.
- Species:
- cat
Plain-English summary
A group of cats with feline infectious peritonitis (FIP) were treated with a medication called GS-441524 for either 42 or 84 days. Most of the cats showed quick improvement, but some experienced side effects like diarrhea and changes in blood cell counts. While both treatment durations were effective, more cats on the longer treatment had certain blood changes. After stopping the medication, most side effects improved, but it's important for pet owners to monitor their cats closely during and after treatment.
People also search for: cat FIP treatment GS-441524 · feline infectious peritonitis symptoms · cat diarrhea after medication
Abstract
The nucleoside analogue GS-441524 is a common treatment for cats with feline infectious peritonitis (FIP). In a previous study, 40 cats with FIP with effusion were treated with 15 mg/kg GS-441524 orally once daily for either 42 days or 84 days, and a 42-day treatment was as effective as the earlier recommended 84-day treatment. The aim of the present study was to describe unexpected clinical and laboratory observations occurring during and after treatment (within one year) in these cats and to compare them regarding the different treatment durations. Thirty-eight cats recovered rapidly during treatment, two cats had to be euthanized, and one cat was lost to follow-up. During treatment, 25 cats developed diarrhea. Lymphocytosis occurred in 26/40 cats during treatment, eosinophilia in 25/40 during treatment, increased alanine aminotransferase activity in 22/40, alkaline phosphatase activity in 7/40, and symmetric dimethylarginine levels in 25/40. These unexpected observations occurred equally in both treatment duration groups, but statistically significantly more cats developed lymphocytosis and eosinophilia when treated for 84 days. Although most of the unexpected observations during GS-441524 treatment improved or disappeared after treatment termination, these conditions have to be monitored, and treatment should not be given for longer than necessary.
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Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/41012609/