Adequan Treatment for Arthritis

and Other Joint Diseases

Randy Walker DVM

About Adequan®…

Adequan® is the common trade name for a compound who’s chemical name is polysulfated glyosaminoglycan (abbreviated PSGAG). Adequan® has been developed and marketed in the past as a treatment for joint injuries in race horses but has also become popular in canine (dog) medicine in recent years for joint problems in dogs. Adequan® is also sometimes used in cats. Adequan® is only one of several newer arthritic medications on the market today and your veterinarian may prefer something different based on your dog’s particular situation.

Is Adequan® A Corticosteroid (such as Cortisone, Prednisone, etc.)?


Is Adequan® A Pain Killer (similar to Aspirin, Phenylbutazone, Tylenol®, etc.)?

No. However, joint pain relief usually does occur due to the effects of Adequan® in the joints. In other words Adequan® improves the conditions in the joint that led to the pain in the first place rather than just masking the clinical signs like pain killers do.

What Is Adequan®?

Adequan® (polysulfated glycoseaminoglycan) is a cartilage matrix substance (meaning it’s made of the same material as the joint cartilage itself) that has been processed into an injectable medicinal form (meaning given as a “shot’).

Briefly, Describe The Normal Anatomy Of The Hip Joint And How This Is Different In The Arthritic Joint.

Normal Hip Joint

Normal Hip Joint

The normal hip joint is a ball-and-socket joint in which the end of the thigh (femur) bone (the “ball”) sits in the socket of the hip. Normally these bones have very smooth surfaces which are covered by a very tough, slick cartilage material. This cartilage allows the bones to glide past each other very smoothly when the dog walks. Also, surrounding this joint, there is a tough, fibrous sack called the joint capsule. This joint capsule is normally filled with a thick joint fluid (called synovial fluid) which lubricates the joint and acts similar to a fluid-filled shock absorber. In the dog with arthritis of the hip joints (usually secondary to canine hip dysplasia but not always) there are many changes, the main ones being: (1) the bone surfaces become rough and rub and grind against each other; (2) the cartilage surrounding the bones wears out and permits more bone-to-bone grinding which leads to more arthritis and at a faster rate; and (3) the joint fluid becomes thin & watery, allowing more friction in the joint leading to even more arthritis and pain.

What Does Adequan® Do?

Adequan® enters the dog’s bloodstream and deposits in the various joints of the body, primarily the hip-joints, where it replaces the cartilage in the arthritic joint and also thickens the fluid surrounding the joint. In his way Adequan® separates the bone surfaces so they aren’t rubbing against each other as much and also “lubricates” the joint. This allows greater mobility of the joint, reduces the pain, and slows the progression of the arthritis.

Does Adequan® Cure Arthritis?

No. There is no cure for arthritis but Adequan® can slow it down and ease the pain in a majority of cases.

Has Adequan® Received FDA Approval For Use In Dogs?


What Are The Side Effects With Adequan®?

Occasional residual pain at the injection site lasting a day or two is the only common adverse side effect that has been noted. This residual pain at the injection site is common with any injection of any medication. Keeping in mind that side effects are possible with any medication, nutritional supplement, or food substance which is taken into the body, Adequan® has proven to be relatively free of side effects in the experience of the growing number of veterinarians who are using it.

How Does Adequan® Differ From The Older Forms Of Arthritis Therapy?

Older forms of arthritis therapy almost universally dealt with reducing pain and did nothing to change the underlying factors responsible for the pain in the first place. In fact, we have learned in recent years that some medications (especially the cortisones) can speed up the arthritic process even through they reduce the pain in the short term. Adequan® differs from these older forms of therapy in that it actually works to “remodel” the joint and reduce the cause of the pain rather than just mask the clinical signs.

How Is Adequan® Given?

We give Adequan® as an injection deep in the thigh muscle.

What Is The Protocol For The Adequan® Injections?

This will vary from patient depending on the specific joint problem(s) encountered. The most common protocol for a typical case of arthritis in the hips is to give a series of two Adequan® injections per week for four weeks (a total of eight injections initially) usually followed by a booster every 60 days. In severe cases the booster injections are given more frequently.

Why Do You Give An Initial Series Of Two Injections Per Week For Four Weeks?

We give several injections because the joint can only use a certain amount of the Adequan® at a time for cartilage rebuilding and the rest is excreted in the urine. For this reason we must add to and gradually build upon the cartilage we lay down each week in order to restore cartilage to the joints. Four weeks is the typical rule of thumb for many cases; how Adequan® is used for a particular case may vary from what I describe here.

If My Dog Appears To Improve After The First Couple Of Weeks Or So On The Adequan® Series Do We Still Need To Get All Eight Injections?

Yes, it’s strongly recommended that we complete the initial series. Although improvement is sometimes noted early on, it usually takes the full (eight) 8 weeks in order to build the cartilage up as much as possible.

Why Do You Recommend A Booster Every 60 Days?

This again is a rule-of-thumb but it appears to work best for most patients. The initial Adequan® series will replace much of the cartilage in the joint and thicken the joint fluid. However, as the joint is flexed (every time your dog moves) the cartilage will gradually wear out again and the joint fluid will become thin. We find that a booster injection of Adequan® every 60 days replaces this cartilage after it becomes lost. We’ve experimented with longer intervals but 60 days appears to be the maximum time period between injections that will still maintain adequate levels in the joint. Severe cases sometimes need more frequent injections. A good analogy is to think of Adequan® as being like the tread on your car’s tires or the oil in your car’s crankcase. Periodically your tires get worn out and have to be replaced and your oil gets thin and needs to be replaced also. The same is true of the arthritic dog’s joint cartilage and joint fluid. With use they wear out and need to be replaced.

What Would Happen If My Dog Improves On The Adequan® Series But We Don’t Get The 60 Day Boosters?

In most cases the patient will gradually return to the original state of lameness over a period of months.

What Is Recommended If The Patient Reverts Back To Lameness After Not Getting The Recommended Boosters?

In most of these cases the lameness has returned because the cartilage has worn out again and often we are in the same position we were in originally with these joints. For this reason a series of weekly injections is again indicated and we sometimes need all eight again.

How Effective Is Adequan®?

We estimate that about 90% or better of patients will respond to Adequan®. As with all arthritis treatments we will occasionally see dogs who do not respond to Adequan®. Adequan® is always given on a trial basis and the results must be evaluated separately in each case. Of course the response will vary from patient to patient.

How Far Into The Adequan® Series Should I Begin To See An Improvement In My Dog?
This varies from patient to patient. Some dogs show a dramatic improvement after the first l or 2 injections while some don’t show improvement until toward the end of the series. Of course, as mentioned before, up to 10% do not.

Since Its Been Stated Before That There Is No Cure for Arthritis, What Is Considered To Be A “Success” With Adequan® Injections?

We consider it a “success” when we have reduced the pain and increased the mobility of the joints. This will vary from patient to patient. It is uncommon for the signs of arthritis to go away entirely.

Is Adequan® The Answer For All Joint Problems In Dogs?

No. Adequan® works best for arthritis and/or dysplasia of the hip joints. It has some effectiveness on arthritis in the stifle (knee) joints and very little effectiveness for most other joint problems.

- Randy Walker DVM
Sun Lakes Animal Clinic
May 14,2004