Success Story – Umbreon

November 14, 2025

FIP Success Story - Wet Neurological FIP

Umbreon, an 8 month old, 2.23 kg spayed female Domestic Shorthair mix cat, presented at emergency on August 27th, 2024, with lethargy, reduced appetite, mild depression and a fever of 39.9 C. An ultrasound showed a small amount of fluid in her abdomen and a focal area of lung changes on the right side. Wet FIP was suspected from Umbreon’s symptoms, previous family history, and bloodwork abnormalities, such as elevated globulin, low albumin and anemia.

Umbreon was given GS-441524 tablets during her overnight stay. By the morning her fever had gone down, energy was increased and her appetite was back. She was released from emergency that afternoon.

September 2nd, Umbreon was showing issues with walking and tripping. Updated videos showed signs of neurological FIP, in particular with her hind legs. September 11th, Umbreon was diagnosed with neurological FIP and her GS dosage was immediately increased (from 15 mg/kg/day) to 10 mg/kg every 12 hrs for a total of 20 mg/kg/day. Umbreon also had an umbilical hernia discovered in her physical exam. Her hernia was to be monitored due to her being in treatment for FIP. At 2.47kg, Umbreon was also starting to gain weight. By the end of September, Umbreon was a whole new kitten, playing with toys on her own and finally getting zoomies.

October 2nd, Umbreon’s bloodwork was improving. October 6th, Umbreon was at 3.11kg, and she was looking less skinny and starting to fill out more. Her eyes that usually showed her third eyelid were looking healthy and full. Near the end of October, Umbreon had higher energy levels and always was wanting to play and eat. At this point, only 1 hind leg was showing slight delays in motor function when walking.

November 4th, Umbreon was still healthy but was showing signs of separation anxiety. She was starting to learn how to stalk and pounce on her own. November 12th her dose was 1 full pill every 12 hours, her one hind leg was still showing issues with motor function. November 19th at 7:30pm was her last pill and Umbreon now entered observation. November 22nd, Umbreon was 4kg and experienced no issues during observation. Her bloodwork had also completely resolved.

On December 10th, Umbreon’s hernia was causing her some pain, but it was advised to wait till her next bloodwork to decide next steps. December 17th, Umbreon’s bloodwork came back perfect with zero signs of FIP. Umbreon was now FIP free!

Umbreon went for hernia surgery on January 10th, and recovered smoothly. She no longer has any issues when walking. She has a weaker immune system than other cats so unfortunately she developed a UTI. Other than that Umbreon has been thriving with tons of energy.