NSAIDs marketed for human use may not be safe for other species, so do not give your pet any medication that has not been prescribed by your veterinarian. The most common side effect of NSAIDs is gastrointestinal irritation (stomach upset) and ulcers. In addition, kidney and liver damage has been reported on a rare occasion. If your pet is taking NSAIDs, you should report any sign of nausea, vomiting, diarrhea or loss of appetite to your veterinarian, and the medication should be discontinued. NSAIDs can have unexpected side effects in certain individuals. Pets receiving NSAIDs on a regular basis should have regular blood and urine tests to monitor for toxicity.
Stronger pain relievers may be required in severe or advanced cases of osteoarthritis. Some of the drugs that may be indicated to allow a patient to function or even exercise more comfortably include Tramadol (a narcotic), gabapentin or amantadine (drugs that modify pain perception) or Duralactin (a dried milk protein concentrate derived from hyperimmunized cows).
Administration of joint supplements can be helpful. Glucosamine and chondroitin sulfates such supplements. Although these supplements have been around for more than 20 years, they have only recently gained widespread popularity. Omega-3 and 6 essential fatty acids (EFAs) are also gaining popularity in the management of osteoarthritis.
Sources of Omega-3 and 6 include fish oils (especially salmon oil), as well as oils derived from flaxseed, avocado and soybean. Special dog foods are now being formulated with these ingredients to promote maximum joint health. Unlike NSAIDs, human supplements can be given at home, though there is no regulation of nutritional supplements. As such, consumers should be aware that there may be no guarantee of product purity or consistency between manufacturers or batches.
Furthermore, your veterinarian may recommend injecting the precursors to joint fluid into the joint space. Hyaluronic acid, or hyaluronate (Legend®, Hi-Visc®), and polysulfated glycosaminoglycan or PSGAG (Adequan®) injections may improve the quality of the joint fluid by providing a source of these joint fluid building blocks. It is presumed that healthy joint fluid means better lubrication and nutrition to the articular cartilage. Although the hyaluronate and PSGAG molecules may only be present for a few days to a week, the effects may be more long lasting. A loading schedule of weekly and twice-weekly injections may be needed initially.
Stem cell therapy is gaining favor as a minimally invasive treatment option for osteoarthritis. Fat is surgically harvested from your pet. This fat tissue is processed and undifferentiated precursor cells (stem cells) are isolated and concentrated. This process may require a few days, and afterward these cells are then injected into the affected joint. These are your pet's own cells and thus pose no risk of transmitting disease or rejection. Surplus cells are stored at sub-freezing temperatures and can be injected at later dates without the need to surgically harvest more fat.
Alternatively, actual stem cells can be retrieved from bone marrow, sent to the laboratory and cultured. After two to three weeks in cell culture, enough stem cells have grown to be injected into the affected joint. Although growth of new healthy cartilage is not expected, clinical improvement may be noted for many months. Stem cells might be expected to be most effective when combined with surgeries that alter the biomechanics of the joint.
Platelet rich plasma (PRP) is also gaining some interest for treating musculoskeletal injury and osteoarthritis. For this process, a blood sample is drawn from the patient, spun down in a special centrifuge and separated into various layers or components. The plasma layer that has high concentration of platelets is retrieved and injected into the affected tissue. This is PRP. PRP is not stem cells, but like the fat derived cells, it is a stimulator or recruiter of the body's own healing mechanisms.
Radiation therapy can also be used to decrease the pain of a joint by damaging the nerve endings responsible for pain sensation.
Despite all available treatments, there is no known way to reverse osteoarthritis. In the end, when nonsurgical management is no longer effective in controlling the clinical signs, surgeries – such as off-loading osteotomies (cuts made in the bone to shift the weight to healthier regions in the affected joint), partial or total joint replacement (Hip, Knee and Elbow joints can now be replaced), joint excision ("Excision Arthroplasty"), joint fusion (Arthrodesis), or denervation (Neurectomy) – may offer return of pain-free use of the affected limb. Your pet’s surgeon can discuss appropriate medical and surgical options with you in more detail.