Frequently Asked Questions

Is there a vaccine for FIP?

One licensed FIP vaccine is available, but its effectiveness in preventing FIP is highly questionable. The American Association of Feline Practitioners Feline Vaccine Advisory Panel does not recommend it. Current research is underway at UC Davis to develop a new vaccine that shows considerable promise.

What happens if my cat misses a daily dose of GS-441524?

Missing one dose is not serious because effective blood levels are sustained over 24 hours. However, missing a dose should be avoided if possible and not become habitual, so the cat doesn’t lose those sustained blood levels of the drug.

Is it necessary to administer the dose at the same time each day?

There is some flexibility in dosing, as with human medicine’s general rule of thumb: “One hour early or one hour late.” It’s best not to avoid inconsistent dosing, but we also understand that daily life can throw curveballs. Adjust accordingly when this happens, but not habitually.

My GS shipment is running late, or I didn’t order in time. What should I do?

You can reduce the dosage by half that day rather than skipping a day, but this should not become a routine practice. Please be proactive and don’t wait until the last minute to order. Alert your treatment advisors and veterinarian (if using prescribed compounds) to determine if any alternatives are locally available.

Is completing 12 weeks necessary even if my cat is “back to normal” now?

There’s no simple test to diagnose FIP, as there’s no test to determine if the virus is eradicated. The twelve-week treatment period is based on well-documented field trials. Undoubtedly, some cats aren’t cured even after 12 weeks, and there’s evidence that some cats are cured sooner. Early cessation of treatment leads to a higher chance of relapse. The best opportunity for a permanent cure and no retreatment is to finish the twelve-week course.

Can I give my cat GS-441524 to eliminate feline coronavirus and keep my cat from developing FIP?

Dr. Pedersen vehemently advises against using GS-441524 to eliminate FCOV. NOT all FCOV mutates into FIPV; therefore, misuse of antivirals can cause drug resistance in cats.


I got my cat as a kitten, and FIP occurred before we could spay or neuter it. When is the best time for surgery?

Spay and neuter procedures can be completed during the tenth week of treatment while still covered by the GS treatment. You may also postpone until after the twelve-week observation period. According to Dr. Pedersen's recommendation, surgeries stress the cat's immune system and could cause treatment setbacks. However, the heat cycle may be more stressful for the cat than the procedure, and male cats also begin spraying, a behavior that can be difficult to stop once it starts. If the cat is in good health and the lab results show significant improvement by the 10th week, please consult your veterinarian to schedule the procedure accordingly. Many vets book weeks to months in advance, so don't wait too long to ask for a scheduling appointment; otherwise, it will have to happen after the twelve-week observation period, when the threat of relapse is most unlikely.

How can breeders help stop the development of FIP in pedigreed catteries?

Breeders can decrease the incidence of FIP by isolating weaned kittens from the queen to avoid exposure to the FCoV and by not mixing very young kittens with older kittens. Limiting coronavirus exposure until 12-16 weeks of age, when the immune system is better developed, lessens the likelihood of kittens developing FIP.

Breeders should avoid matings between cats with close relatives who've died of FIP or who've produced known kittens that developed FIP. Researchers have yet to identify a specific genetic component, and until that happens, breeders must take every precaution to prevent the production of more cats that develop FIP. Lastly, follow accepted vaccination protocols and practice good husbandry to limit other infections that weaken the cat's immune system, predisposing kittens to secondary illnesses that can trigger an FIP mutation.

How much money is needed yearly for FIP research, and how can I help?

All money donated to SOCK FIP is directly allocated to FIP research. $50,000 – 75,000 a year supports a single technician or graduate student, and the more students the CCAH can engage in research, the faster they can reach their goals.

While SOCK FIP funds UC Davis for greater impact, the scientific community is collaborative. Other groups raise money to study FIP, which is highly respected. Researchers have studied FIP for over 50 years, and while we now have a better understanding of it, the dilemma of preventing and curing FIP remains, necessitating a collaborative, worldwide effort.