Autologous-Conditioned Serum (ACS or IRAP™ II) Therapy
What is ACS for horses?
ACS is a blood product containing concentrated amounts of an anti-inflammatory protein called interleukin-1 receptor antagonist protein (IRAPTM II). It is most commonly used to treat the early stages of osteoarthritis.
What does ACS therapy do for lameness in horses?
The interleukin-1 receptor antagonist protein is injected into the affected joint, slowing the inflammatory process that leads to and perpetuates cartilage damage and osteoarthritis. Unlike repeated injection of cortisone-like steroids, IRAPTM II may be used repeatedly without detrimental effects to the cartilage. If used early in joint disease, IRAPTM II may prevent early progression and development of osteoarthritis which may prolong the performance years of your horse and prevent early retirement, as well as decrease the need for continued veterinary treatment and costly therapies.
ACS Therapy at UF
Two forms of IRAP/ACS are available at UF. IRAPTM II is made by incubating blood from the patient for 24 hours. The horse remains at the hospital overnight and the first treatment can be performed the following day. Additional samples can be shipped to the primary care veterinarian for follow-up treatments.
The affected joint is usually treated every 7-10 days for three or more treatments. The amount of IRAPTM II injected depends on the size and location of the joint. Rest is typically recommended following each injection.
- Learn about stem cell therapies
- Learn about platelet-rich plasma (PRP) therapy
- Return to UF Equine Lameness & Imaging
- Contact the UF Large Animal Hospital to see if ACS therapy can help your horse