Sodium Hyaluronate

Drugs and medications image
Drugs and medications image EquiMed


SOH-dee-uhm heye-ahl-UREN-eyt - Pronunciation guide

Brand Names

  • Hylartin® V
  • Legend®


Sodium hyaluronate is a compound found normally in connective tissues, the umbilical cord, synovial or joint fluids and in the vitreous humor or fluid filled part of the eye. It is also a major part of the capsule of the bacterial species Streptococcus. Because this compound is normally found in the horse's body, it should not create any immune reaction when a horse is treated with it.

Sodium hyaluronate helps to maintain joint health. It acts to inhibit inflammatory responses and improves the lubrication of the joint fluid. This is a prescription medication. Clinical trials indicated 90 percent or higher positive responses in horses treated with sodium hyaluronate, either intravenously or intraarticularly, for joint arthritis.


Sodium hyaluronate is used both intravenously (injection directly into a vein) and intraarticularly (injection directly into a joint space). Most products are approved for use in the fetlock and carpal (knee) joints, though they can be used in other joints off label. The goal in using sodium hyaluronate is to improve the health of the joint. It is useful for horses with some bony arthritis. Inflammatory responses will be minimized and the viscosity of the joint fluid improved.

This medication would not be helpful for a horse with an infectious cause of joint inflammation. It should also not be injected into a joint with an associated fracture. Stall rest for at least 48 hours is recomended post treatment.

Treatment may consist of one or repeated injections. No more than three injections total are recommended. Injections should be given at weekly intervals.

Dosage and Administration

Prescription medicationSodium hyalruonate
Method Dosage
(click row for calculator)
Concentration Period Duration
Intravenous injection 40 mg 10 mg/ml Weekly 3 weeks
Intra-articular injection 20 mg 10 mg/ml Weekly 3 weeks


  • Federal law restricts this drug to use by or on the order of a licensed veterinarian.
  • For intravenous administration, use aseptic technique and inject slowly into the jugular vein.
  • Legend Injectable Solution 2 mL: Strict aseptic technique should be observed when administering by intra-articular injection. As with any intra-articular procedure, proper injection site disinfection and animal restraint are important. Excess joint fluid should be aseptically removed prior to injection. Care should be taken to avoid scratching the cartilage surface with the tip of the injection needle. Diffuse swelling lasting 24 to 48 hours may result from movement of the needle while in the joint space.
  • Extra-label use of drugs in treating animals is allowable only by licensed veterinarians within the context of a valid veterinarian-client-patient relationship, and does not include drug use in treating animals by the layman (except under the supervision of a licensed veterinarian).
  • The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your equine appears to feel better, the entire treatment plan should be completed to prevent relapse.
  • This medication may be available in forms and concentrations not noted in the above table. Always check the label and literature provided with the medication about the form and concentration and DO NOT USE the calculator if the information differs.
  • Calculator is for educational purposes only. Follow your veterinarian's instructions regarding use of this, or any medication.

Side Effects

While no side effects were noted during clinical trials, some reports of minor adverse reactions have come from use in the field. These include swelling at the joint injection site with associated lameness and pain. With intravenous usage, there have been reports of fever, lethargy and depression. Reactions were generally gone in 24 to 48 hours and considered to be minor.


Sterile technique must be maintained at all times when using this medication either intravenously or intraarticularly. Injections should not be made through skin that has recently been fired, has counterirritant present or has been blistered. Radiographs (x-rays) should be used to verify that there are no fractures associated with the joint before any injections are made.

The cartilaginous surfaces of the joint should not be scratched by the needle during injection. This can cause temporary swelling and pain.

This medication has not been tested for safety in mares or stallions used for breeding, pregnant mares or lactating mares.

Some preparations of sodium hylauronate are only approved for intravenous usage and should not be injected into joints.


There are no known contraindications for use of this compound with other medications. This medication should not be used in horses intended for human consumption.


Systemic toxicity has not been shown for this compound, however injection of large doses into small joint spaces could cause temporary swelling and pain.


About the Author

Deb M. Eldredge, DVM

Deb M. Eldredge, DVM is a Cornell graduate and horse lover from early childhood. She was active in 4-H and Pony Club, riding mostly huntseat but also Western. She has competed in various horse show venues as well as competitive trail rides and small three day events. At Cornell she was a member of the Women's Polo team.

Dr. Eldredge is a national award winning writer from both the Cat Writers Association and the Dog Writers Association of America. She lives in upstate NY on a small farm with 3 elderly horses, 1 miniature horse and 2 donkeys as well as various other animals.

Visit Deb Eldredge's Google+ Page