Arthritis and Cats: Can Drugs Really Ease the Pain?
Arthritis is an unfortunate and nearly ubiquitous feature of aging. The most common form occurs as the tissues and structures in joints degenerate naturally. This process, called degenerative joint disease (DJD), leads to stiffness, pain, decreased range of motion, and limping on affected limbs.
Arthritis is very common in older individuals of almost every vertebrate species. Elderly humans and elderly large dogs are sometimes debilitated by the condition. As a result, medications are commonly used and prescribed in human and canine medicine.
Cats also suffer from arthritis, but when it comes to treating it, cats are simultaneously lucky and unlucky. They are lucky because they are small creatures, which are much less likely to be debilitated by arthritis. They are unlucky because most of the medications that are available to other species cannot safely be used in cats.
First, let's cover the lucky individuals: Many cats with arthritis suffer no significant symptoms and require no treatment. An elderly cat may come to my office for vomiting, and X-rays will show significant arthritis in the hips. If the cat is not showing symptoms or pain, then no treatment is recommended. In my experience, the majority of cats with arthritis fall into this category:
However, there is an unlucky minority with significant symptoms, which may include limping, inability or reluctance to jump up or down, decreased activity, or visible pain and distress when using an affected limb. Unfortunately, there are limited treatment options for cats in this situation.
The mainstay of arthritis treatment in humans and dogs is with nonsteroidal anti-inflammatory drugs (NSAIDs), painkillers that reduce inflammation in joints. Common veterinary NSAIDs include aspirin, carprofen (Rimadyl), meloxicam (Metacam), and deracoxib (Deramaxx). Of these, only aspirin is generally considered safe for long-term (or even short-term) term use in cats, and the wisdom of using it is still debated among veterinarians.
Cats lack an enzyme system in the liver to metabolize most NSAIDs, and are extremely prone to toxicity from them. Aspirin, when used, must be used at low doses. It's usually given only every 72 hours; even then, toxicity can still occur. Some cats do not tolerate aspirin, and large numbers of cats get no significant clinical benefit. Meloxicam was once touted (and labeled) as safe for cats. It was widely used until large numbers of adverse reactions were reported and the labeling was changed.
In short, NSAIDs aren't especially practical for use in feline arthritis. However, there are some options.
Nonmedical treatment options are always a good place to start. Overweight cats suffer greater arthritis symptoms than their thinner counterparts, so weight management should be incorporated into any arthritis management protocol (unfortunately, weight management can be challenging in cats). Physical therapy, such as range-of-motion exercises, muscle strengthening activities, and gentle massage, may be beneficial. Omega-3 (fish oil) supplementation is controversial, but many owners have reported favorable results. Dietary supplements such as glucosamine are even more controversial, and some experts worry that cats may be at high risk of toxicity.
Although NSAIDs aren't frequently used in cats, some painkillers are considered safe. In particular, buprenorphine is often effective. It is administered as a liquid onto the gums (it is absorbed without being swallowed) and can bring significant relief. Other cats do well with tramadol.
Finally, as a last resort, some cats receive steroids such as prednisolone to treat arthritis. Long-term use of steroids is a big no-no in dogs and humans. Although steroids can lead to significant side effects in cats as well, feline companions generally tolerate these drugs much better than dogs or people. Steroids often provide significant improvement, so the benefits of their use can outweigh the risks.
It is likely that medical breakthroughs will lead to safe treatments that will render arthritis irrelevant. Unfortunately, until then, cats with clinical arthritis will have limited options.