Arthritis and antioxidants:
A search for new treatment

By Ashley Mitek

AS Fido rolls out of bed in the morning, you may not hear moans and groans, but other signs of arthritis may be lurking such as being stiff to rise or having difficulty going up stairs. Pfizer Animal Health studies estimate that one in five dogs will suffer from the disease, but yet only 50 percent of dogs receive treatment.

Dr Wanda Gordon-Evans, a veterinary surgeon at the University of Illinois Veterinary Teaching Hospital explains that, "The current treatment for arthritis pain is non-steroidal anti-inflammatory drugs or NSAIDS," like aspirin and the more commonly-used prescription in veterinary medicine, Rimadyl.

Most of these drugs work by inhibiting an enzyme that makes prostaglandin, a messenger molecule that is part of the inflammation process. The logic is, if the pathway leading to inflammation by the body can be blocked, pain can be prevented or reduced.

While these drugs have been the first line of defense against arthritis for decades, they can cause harmful side effects such as stomach ulcers as well as liver and kidney problems. "It would be great if we could find a drug that had no adverse effects, yet still help with arthritis," says Dr. Wanda Gordon-Evans about her decision to investigate a new compound called S-adenosyl Methionine or SAMe for short.

This new antioxidant is a "nutraceutical," meaning it is not regulated by the FDA like the more commonly known glucosamine and chondroitin supplements. In human studies, SAMe has been shown to have some effect on arthritis and has even been tested for its use in treating depression.

Dr Gordon-Evans explains that, "because part of the pathophysiology behind arthritis may be helped by antioxidants, we think this drug has the ability to improve a dog's quality of life." She also mentions that because this drug is an antioxidant, it is highly recommended for dogs with liver disease, one of the side effects of NSAID therapy.

Right now she is in the midst of a clinical trial evaluating around 30 dogs to see if SAMe helps with their arthritis. Part of the trial consists of having the owners bring the dog in every three weeks to be walked across a special weight sensing mat that measures how much pressure is placed on each foot, where exactly the weight is placed, and for how long.

"We can tell from looking at the computer images of weight placement how the dog is compensating for its painful arthritis," explains Dr Gordon-Evans. She goes on to mention that dogs with arthritis distribute their weight in different ways since, in contrast to humans, they have three other legs to share the burden.

For example, "a dog that is lame in its front right leg may just shift its weight to the front left and spend more time off of its front right, or he may start to shift the weight to its hind limbs," explains Dr Gordon-Evans.

As always, contact your veterinarian if you have questions. Although many owners want to alleviate their pet's pain if they notice a limp, do not attempt to medicate your animal with over-the-counter medications without the guidance of a veterinarian.

An archive of Pet Columns, including the above, from the University of Illinois College of Veterinary Medicine is available online at www.vetmed.illinois.edu. Many thanks to the College for their kind permission to reprint.