Polyprenyl Immunostimulant™

What is Polyprenyl Immunostimulant™?

Polyprenyl Immunostimulant™ is manufactured by Sass & Sass, Inc. and is the only therapeutic approved by the USDA for the treatment of feline rhinotracheitis. It reduces the severity of the disease in cats. It is a very safe, well-tolerated oral liquid designed with cats in mind. Polyprenyl Immunostimulant™ is formulated as a 2 mg/mL solution of phosphorylated polyprenols and is offered in 10 mL vials or packs of 6 x 10 mL vials. 

Polyprenyl Immunostimulant™ works by upregulating innate immunity and directing cellular immune response. It is a very safe product which aids in the reduction of clinical signs resulting from rhinotracheitis infection in cats 8 weeks of age or older. Polyprenyl Immunostimulant™ is often referred to as PI or PPI.

Polyprenyl Immunostimulant™ reduces the severity of clinical signs resulting from feline herpesvirus infection (URI, FHV-1, FVR, FRV) in cats eight weeks of age or older.​

Polyprenyl Immunostimulant™ is administered orally; a single dose equals 0.25 ml/kg. The recommended dosage is two oral doses of Polyprenyl Immunostimulant™ daily for 15 days.​​

Safety studies in 390 cats showed that oral administration of 0.5 mg/kg of Polyprenyl Immunostimulant™ twice daily for 15 days is safe for cats eight weeks of age or older. No signs of illness were note in toxicity tests conducted at 5 mg/kg dose of Polyprenyl Immunostimulant™.​

Polyprenyl Immunostimulant™ is the only USDA-approved oral treatment for feline rhinotracheitis. No analogs or similars exist.
• 100% sourced and manufactured in the USA.
• Exceptional safety record: no adverse events reported during studies or seven years post-market introduction.
• Small volume of liquid is easy to administer to cats.​

Polyprenyl Immunostimulant™ Research

Feline Viral Rhinotracheitis and URI Research, Trials, and USDA Regulations.

Veterinarians and customers often ask questions about Polyprenyl Immunostimulant™ trials. Our  past, current, and planned Sass & Sass, Inc. clinical studies and trials that involve Polyprenyl Immunostimulant™ (PI, PPI) are listed here.

Feline Infectious Peritonitis (FIP) Research, Trials, and USDA Regulations.

Veterinarians and researchers also study and experiment with Polyprenyl Immunostimulant™ in other infections and other species. You may read about FIP research here.

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