What is CureFIP™ Oral Capsule?
CureFIP™ Oral Capsule is a dual-antiviral treatment for Feline Infectious Peritonitis (FIP). Each capsule contains a precisely measured combination of GS-441524 and EIDD-1931, formulated to inhibit FIPV replication and reduce the risk of the virus developing resistance during treatment.
Why does CureFIP™ contain two antivirals?
GS-441524 alone is highly effective against FIPV, but as with many viral diseases, prolonged single-agent treatment carries a risk of the virus developing resistance over an 84-day course. EIDD-1931 works through a complementary mechanism, making it significantly harder for the virus to mutate and adapt. The combination improves treatment reliability, particularly in cats that require extended treatment durations.
What is EIDD-1931?
EIDD-1931 is a broad-spectrum antiviral that works by inducing errors in viral RNA replication — effectively causing the virus to make fatal copying mistakes. It has been studied extensively in the context of RNA viruses and complements the mechanism of GS-441524 in a meaningful way.
What forms of FIP can CureFIP™ Oral Capsule treat?
CureFIP™ Oral Capsule is effective for wet (effusive) and dry (non-effusive) FIP. Cats presenting with neurological FIP — symptoms affecting the brain or spinal cord — typically require injectable formulations at higher concentrations. Consult your veterinarian to confirm the appropriate treatment format for your cat's specific FIP type.
How is CureFIP™ Oral Capsule different from CureFIP™ injectable?
Both products contain GS-441524 as the primary antiviral. The oral capsule offers a needle-free alternative that many owners find easier to administer consistently over an 84-day course. The capsule formulation also includes EIDD-1931 for resistance prevention. The injectable remains the preferred option for neurological FIP and for cats who cannot reliably receive oral medication.
How do I give my cat the capsule?
The capsule can be administered directly by mouth, hidden in a small amount of food, or using a pill popper device. Watch our instructional video for practical techniques to make daily dosing as stress-free as possible for both you and your cat.
What if I miss a dose?
If you miss a dose, give it as soon as you remember on the same day. If you only remember the following day, skip the missed dose and continue with the regular schedule. Do not double dose. Consistent daily administration is critical — avoid skipping doses where possible.
How long is the treatment?
A minimum of 84 days is required — equivalent to three packs. Some cats, particularly those with severe or neurological FIP, may require a longer course. Your veterinarian will assess your cat's response throughout treatment and advise on whether an extended course is necessary.
How will I know the treatment is working?
Most cats show clear signs of improvement within the first pack. Early positive indicators include returning appetite, increased energy and physical activity, reduction or resolution of fever, and resumption of normal self-grooming. Weight gain typically follows as your cat's condition stabilizes and improves.
Can CureFIP™ be used alongside other medications?
Yes. GS-441524 is an antiviral and is generally compatible with supportive medications used to manage FIP symptoms. Two exceptions: lysine is not recommended for concurrent use during treatment, and interferon has not been shown to have any beneficial effect on FIP and should not be used as a substitute or supplement to CureFIP™. Always inform your veterinarian of all medications your cat is receiving.
Do I need a veterinarian to start treatment?
A confirmed or strongly suspected FIP diagnosis is important before beginning treatment. We strongly recommend working with a veterinarian throughout the 84-day course to monitor your cat's response, track weight changes, and manage any side effects. That said, we understand that access to FIP-experienced veterinarians varies by location — our team is available to support you through the treatment process.
What should I feed my cat during treatment?
Fresh, natural foods are well tolerated — cooked fish, chicken, and other whole-food options support recovery and are generally palatable to cats regaining their appetite. If your cat develops diarrhea during treatment, switch temporarily to dry cat food for a few days until the episode resolves. Maintaining good nutrition throughout the treatment course supports your cat's immune recovery.
Are there any side effects?
GS-441524 has a well-established safety profile in cats. The most commonly reported side effects are mild and transient, including temporary loss of appetite or mild gastrointestinal upset in the early days of treatment. If you observe any severe or persistent side effects, contact your veterinarian promptly.
How many packs do I need for a full treatment course?
A minimum of 3 packs for an 84-day course. We recommend ordering all three packs at the start of treatment to avoid any interruption — consistency of daily dosing is critical to treatment success.
What if my cat's condition does not improve?
Contact us or your veterinarian. In some cases, a switch to injectable formulation or a dosage adjustment may be required. Do not discontinue treatment without veterinary guidance — stopping treatment prematurely is one of the most common reasons for relapse.
What happens after the 84 days are completed?
Your veterinarian will assess whether your cat has achieved remission. Most cats in full remission do not require further treatment. A monitoring period of 12 weeks post-treatment is typically recommended to confirm sustained remission before concluding the treatment program.
Have a question not answered here? Contact our team directly — we're here to support you through every step of your cat's treatment.
