Cat Feline Infectious Peritonitis: Welfare and New Treatment Options

FIP, once universally fatal, can now be treated with antiviral drugs, transforming the welfare outlook for affected cats.

Key Facts

FIP is caused by a mutated form of feline coronavirus and was previously almost always fatal
Antiviral drugs including GS-441524 and molnupiravir have shown cure rates above 85% in clinical studies
Wet FIP (effusive) and dry FIP (non-effusive) present differently but both respond to treatment
Treatment typically lasts 12 weeks with monitoring for relapse for a further 3 months
Cost of licensed treatment is high — unregulated compounded versions exist with variable quality
Young cats under 2 years and those in multi-cat households are at highest risk

Welfare Considerations

FIP caused immense suffering in affected cats and devastating grief for their owners for decades. The availability of antiviral treatments has transformed the welfare trajectory of diagnosed cats — from near-certain death with significant suffering to a strong chance of cure and full recovery. Welfare-centred management starts with early diagnosis (through effusion analysis, PCR testing, and clinical assessment) to begin treatment before severe organ involvement occurs. Access to treatment remains a welfare equity issue — cost creates significant barriers for many owners, and advocacy for affordable licensed treatment is an important welfare cause.

What You Can Do

Seek veterinary assessment immediately if a young cat shows signs consistent with FIP
Ask your vet about both licensed and compassionate access antiviral treatment options
Support organisations providing financial assistance for FIP treatment costs
Advocate for affordable access to FIP antivirals as a welfare equity issue
Reduce risk by limiting exposure of young cats to FCoV in high-density environments