We have been asked frequently the effectiveness of oral form of GS-441524 by cat parents who do not wish to perform daily injections of GS-441524 on their cats. Generally, we don't recommend using oral form of GS-441524 because one simple reason...ABSORPTION.
Feline Infectious Peritonitis virus often damages digestive organs such as the stomach, intestine, kidneys and liver. These damaged organs have reduced ability to digest and absorb GS-441524 into your cat's bloodstream.
Therefore, while oral formulas may reduce the symptoms of FIP in cats, it is difficult if not altogether impossible to know whether sufficient amount of GS is absorbed into the blood stream via the digestive track on a daily basis. When insufficient dosage is supplied into the bloodstream for an extended period, relapse rate increase and treatment often need to be prolonged beyond 12 weeks.
We hesitantly support oral forms of GS only in the following situations:
When your doctor is absolutely certain that your cat's digestive organs are functioning at their 100%
During later stage of the FIP treatment when blood tests show that GS injections have effectively reduced viral infection to a minimum, and all body functions have returned to normal.
When used as preventive treatment for cats that are suspected of FIP infection by the doctor.
When used after the conclusion of the treatment as a periodic immunity booster to avoid relapse.
The most effective method of delivering sufficient amount of GS to your cat's bloodstream is via direct subcutaneous injections. There is no better way.