Pentosan polysulfate (PPS) is a heparin-like, semi-synthetic polysaccharide ester derived from beechwood hemicellulose. PPS is a mild anticoagulant, with anti-inflammatory, fibrinolytic, and hypolipidemic properties.
In veterinary medicine, PPS is used to manage and treat OA. PPS is thought to help preserve cartilage integrity and to improve joint health by supporting anabolic activity of chondrocytes and synoviocytes. It also provides protection from catabolic events within the joint by reducing levels of cytokines and inflammatory mediators within cartilage matrix and synovial fluid.
PPS is used systemically in horses as a part of conservative management/treatment of OA. Studies have shown therapeutic levels in synovial fluid following intramuscular (IM) administration. PPS usually is administered by IM injection once a week for a series of four weeks. It also may be administered intra-articularly.
Pentosan Polysulfate Side Effects
PPS generally is well tolerated.
Horses: Systemic PPS has been shown to elevate PTT for up to 24 hours. When used intra-articularly, there is the possibility of intra-articular bleeding. Appropriate bandaging and rest post injection are recommended.
Dogs: Mild GI disturbances including vomiting, anorexia.
PPS affects clotting time. It should be used with caution in animals receiving anti-coagulants or those undergoing surgery in the near future.
Dosage and Administration
Intramuscular. Administer 6-18ml by intravenous injection as directed by a veterinary surgeon. 1 mL by intra-articular injection. Injections may be repeated once weekly for three to four injections. More than one joint may be treated at a time. Prepare site as for surgery. Avoid iodine based skin preparations. Use a neutral, soapless skin cleanser. A 20 gauge noncutting needle is suitable for injection. Introduce into the joint space with steady even pressure. Allow approximately 1.0 mL of synovial fluid to escape. Attach syringe of Pentosan Equine. Withdraw more synovial fluid into the syringe if possible and inject the joint fluid/Pentosan Equine mixture into the joint. Draw back once or twice and mix Pentosan Equine and the joint fluid within the joint. Note. Pentosan has anticoagulant properties. Any blood vessel, even a small one, will bleed more freely and for longer if a track of pentosan polysulfate is left as the needle is withdrawn, hence the advice that the needle be ‘washed’ with joint fluid before withdrawal from the joint. Blood is the most usual cause of sudden inflammatory swelling following intra-articular injection. Even small amounts may be reactive. Careful technique, avoiding tissue damage and subsequent firm bandaging for three to four hours will minimise risks of intra-articular haemorrhage. After intra-articular administration. Place a firm elastic bandage around the joint after injection and maintain the horse in a confined space for three to four hours. Remove bandage after that time. Rest the horse for two weeks following final injection and follow with a further two weeks of graded walking exercises before returning to work.