Medications for Degenerative Arthritis
Degenerative joint disease is the number one cause of chronic pain in dogs. The condition is the result of long-term stresses on a joint, either resulting from an old injury or from natural development of a poorly conformed joint. While surgery may be able to help in some situations, most of the time the degeneration of the joint cannot be reversed and treatment focuses on preventing progression of damage. Numerous products are available; some are best combined with others and some cannot be combined. What we do know is that arthritis pain is best addressed by what is called a multi-modal approach, meaning that several approaches combined yield better results than any single therapy. Here, we focus on medications.
Slow-acting drugs for arthritis ultimately improve joint function and help with pain relief, but they require a time frame of weeks to months to exert their effect. These products are typically nutritional supplements that have medicinal properties. Most arthritis patients can benefit from their use and they are considered a basic starting level for joint care. These products are not likely to be helpful for spinal arthritis as the joint composition of an intervertebral disc (the joint of the spine) is totally different from those of other bones. There are numerous products available combining glucosamine, chondroitin sulfate, assorted vitamins, creatine (a muscle building block), omega 3 fatty acids and more. Many senior or joint supporting diets are well fortified with glucosamine. Certain dietary fats, typically cold water fish oils, have been found to have anti-inflammatory properties. While this finding has primarily been used in the treatment of itchy skin, many arthritic dogs have also benefited from supplementation. While there are no toxic issues to be concerned with, these products require at least one month to build up to adequate amounts. Effects are not usually dramatic but can be helpful.
Most pets with arthritis pain need relief now, not in 1 to 2 months when the cartilage building blocks and nutritional anti-inflammatories have had a chance to build up. The next mode of therapy is the NSAIDs, or non-steroidal anti-inflammatory drugs. These medications act quickly by suppressing the inflammatory biochemicals that ultimately lead not only to the pain of arthritis but also to cartilage damage. None of these medications can safely be combined with one another. Furthermore, human NSAIDs tend to be toxic to pets. While aspirin has some potential use in relieving joint pain, safer medications developed specifically for pet use have become the standard for joint pain management. Never use a human medication of any kind in a pet without specific instructions on how to do so from your veterinarian. Carprofen (Rimadyl®), Meloxicam (Metacam®), Firocoxib (Previcox®) are NSAIDs commonly used in our dogs. Pre-treatment screening blood tests are still important before using an NSAID as a pre-existing kidney or liver condition may preclude their use. Monitoring tests typically are recommended every six months for pets on NSAIDs. If a pet has or comes to develop a condition that is not compatible with NSAID use, one of the analgesics listed below would be a fair alternative.
The corticosteroid hormones (prednisone, dexamethasone, etc.) create broad spectrum inflammation inhibition including wiping out some biochemical mediators it would be best not to wipe out. The result is relief from just about any type of inflammation: arthritis, itchy skin, immune-mediated disease and more, but in the long run side effects are problematic. Using these medications to control arthritis pain is not desirable in the long term and one of the other medications mentioned would be a better idea. Sometimes the combination of a cartilage-protecting agent and an anti-inflammatory drug is not adequate for pain control. There are several appropriate pain relievers that can be used in pets. These medications are strictly analgesics and do not modify the inflammation in the joint. Tramadol is a narcotic pain reliever similar in many ways to codeine. Amantadine is an antiviral medication found to relieve chronic pain. Gabapentin, originally an anti-seizure drug, has been found to have effects on chronic pain especially pain from pinched or inflamed nerves. The medications are compatible with all other the other medications listed. A synergism occurs when these medications are combined with NSAIDs such that the combination of both drugs produces greater results than one would expect. Adequan Injections have numerous beneficial effects for the arthritis patient including the inhibition of harmful enzymes involving joint cartilage destruction, stimulation of cartilage repair, and increasing joint lubrication. Adequan is given as an injection and so is able to reach all joints but it seems to have a special affinity for damaged joints. Adequan may be combined with any of the other medications discussed.
In conclusion, the arthritic pet has a large menu of medications to select from and while proper medication is an important part of therapy, weight control and proper exercise should not be forgotten. Proper exercise is excellent physical therapy for the arthritic pet, as it is crucial to maintain as much muscle mass as possible to support the abnormal joint. Massage and gentle flexion/extension of the joint may also help. Remember, treatment for joint disease is likely to involve a combination of medications in addition to physical activity.
Article Furnished by Roberta Raymond D.V.M.
Blue Cross Pet Hospital
7615 Fair Oaks Blvd
Carmichael, CA 95608