Using Glucosamine to Prevent Canine Osteoarthritis
This “nutraceutical” is best used early in life to prevent osteoarthritis.
[Updated February 23, 2016]
My Border Terrier, Dash, and I have been enthusiastic agility partners for about four years. It’s difficult to imagine anything more fun than stepping up to the start line at an agility trial and getting ready to rocket around the course with her! Of course, my friends who work with their dogs in flyball, herding, freestyle, obedience, earthdog, lure coursing, hunting, search and rescue, and more, all feel the same way about their dog activity (or activities) of choice.
It can take years to train a dog and to prepare his body for the physical challenges of competition in these sports. Once he’s ready to compete, the goal becomes preservation of his fitness and soundness (physical and mental), so that you both can enjoy your activities for as long as possible. Preventing injury and, as much as possible, the breakdown of structural integrity that accompanies advancing age is a huge challenge.
In recent years, one nutritional supplement in particular has been embraced by competitive dog owners and veterinarians for its ability to meet that challenge. Glucosamine is the best known and most commonly used supplement for prevention of lameness due to osteoarthritis (a.k.a. degenerative joint disease) – a disorder of the joints characterized by progressive deterioration of the articular cartilage.
Your Dog's Joints
For the active dog, mobility is all about the health of the cartilage that forms the protective cushion between a dog’s bones where they meet at the joint. Cartilage provides a spongy, watery pad where the shoulder, hip, knee, elbow, wrist, and other bones come together, acting as a shock absorber between the bones when they are in motion. Like a fluid pillow full of thick liquid wedged between the bones, cartilage consumes the force of the concussion generated during movement.
Cartilage does not have a blood supply; it relies on the motion of the joint to pump nutritive liquid in and out, pulling needed nourishment into the tissue. With age, cartilage can become drier, thinner, and less effective at cushioning the bones in the joint.
Joint problems occur when the rate at which joint cartilage degrades exceeds the rate at which the dog’s body replenishes it. When the supply of cartilage is inadequate for the needs of the joint, bone rubs against bone, inflaming the bone itself and the surrounding nerves, and producing pain and lack of mobility.
Cartilage is a very dynamic substance, constantly turning over and renewing itself, especially in young dogs. So, proper nourishment of the cartilage tissue is important at all stages of an active dog’s life, not just when visible signs of joint degeneration appear.
Many factors can contribute to the net loss of cartilage in a dog’s joints. Hip dysplasia (an improperly formed ball and socket joint in the hip) and osteochondrosis (poor structural integrity, sometimes due to poor breeding) top the list of hereditary conditions. Injuries to the joint as a result of a dislocation, torn ligaments, or even the trauma of surgery may cause cartilage deterioration. Bone “spurs,” or the excessive growth of bone material in the joint, inflame the joint and break down healthy cartilage. Inflammatory and degenerative joint diseases, like Lyme disease, can affect dogs of all ages. And of course, osteoarthritis – the slowly progressing erosion of cartilage due to age or excessive use of the joint – has become one of the most frequently diagnosed health problems in older and highly active mature dogs.
A conventional treatment for the discomfort of joint pain in dogs is the administration of pain-relieving non-steroidal anti-inflammatory drugs (NSAIDs), including aspirin, as well as Rimadyl, Deramaxx, and EtoGesic. These pharmaceuticals temporarily relieve pain but may also produce significant, unwanted side effects ranging from gastric upset and bleeding to liver damage and seizures. All of the NSAIDs have been plagued by reports of serious health problems resulting from their use. But they continue to find a following among veterinarians and dog owners who value their potent and fast-acting pain relief.
Unfortunately, many people do not understand that pain relief drugs may mask escalating joint problems. These products do nothing to heal or stabilize the joint’s destruction; as soon as the drugs are discontinued, the dog again experiences all of the discomfort associated with joint deterioration.
Your Role in Joint Health
Joint cartilage contains an element called glucosamine, an essential building block of healthy cartilage tissue and a key ingredient in cartilage metabolism. A naturally occurring compound in many mammals’ bodies, glucosamine is composed of a sugar and an amino acid, which the body uses in the creation and repair of cartilage. Glucosamine molecules have low compressibility rates, which makes them excellent shock absorbers. These molecules also attract and hold water, which makes them great lubricants.
As joints degrade, a vicious cycle begins. When cartilage suffers damage, the joint area becomes inflamed, thereby releasing enzymes into the joint. These enzymes further break down the cartilage and thin the joint lubricating fluid. The absence of healthy cartilage and the thinning of protective joint fluids make joints more susceptible to injury over time. More injuries add to the cycle of joint deterioration.
A “nutraceutical” or nutritional supplement rather than a drug, glucosamine is extracted from shellfish shells (although there is also a corn-derived version on the market). Available in several chemical forms, including glucosamine hydrochloride and glucosamine sulfate, glucosamine helps to improve joint health by supplementing the nourishment of the cartilage with more glucosamine than the body produces itself.
Therefore, adding glucosamine in the form of supplementation essentially tips the balance in favor of the creation of healthy cartilage, and halts the cycle of net cartilage loss due to overuse, injury, or joint disease. The goal is to provide the tissue with plenty of the component the body uses to produce healthy cartilage cells that quickly replace damaged or lost cells. Glucosamine performs this work by creating an environment that supports cell formation and the thickening of joint fluids.
“Every active dog should be on a glucosamine source,” asserts Dr. Chris Bessent, a Wisconsin-based veterinarian specializing in natural treatment methods for performance horses and dogs. She explains that most athletic dogs have healthy joints that have not sustained damage yet. But, active dogs regularly “push the envelope,” causing some joint inflammation that can develop into early joint breakdown. Dr. Bessent refers to mature, athletic dogs that show the generalized, early signs of joint deterioration as “dogs running on four low tires.” Supplementing with glucosamine, she believes, “pumps up the tires” again.
Dr. Bessent recommends taking a proactive approach to joint maintenance and injury prevention starting when an athletic dog is one to two years old. This is a far-sighted approach that may not be appreciated by most dog owners, especially when they see the price tag on some glucosamine supplements.
Selling people on the value of preventive maintenance is difficult, unless they have had a dog with a promising competitive career cut short by osteoarthritis. This is the point at which most veterinarians will mention glucosamine to their clients, but much of the damage has already occurred. However, even in late-stage osteoarthritis, the supplement may improve matters enough to make it worthwhile.
The pet supply marketplace overflows with all sorts of glucosamine supplements, many containing ingredients that reportedly enhance the positive effects of glucosamine. These supplements come in a variety of forms and dosages, and pricing runs all over the map. Just about every pet supplement manufacturer offers at least one glucosamine product.
Also, many manufacturers add “synergistic” ingredients to the supplement including vitamins C, D, and E; manganese; Omega-3 and Omega-6 fatty acids; and herbs like yucca and alfalfa. Many supplements also contain chondroitin sulfate, which some medical professionals believe aids in holding fluids in the cartilage. Several manufacturers also offer chondroitin sulfate as a stand-alone product of equal importance to glucosamine.
Dr. Bessent has used both glucosamine and chondroitin in her practice for years, and has experienced “huge” clinical successes using glucosamine, and “some” clinical improvement using chondroitin. According to Dr. Bessent, the glucosamine molecules are smaller and probably have a better absorption rate than chondroitin.
Dr. Bessent says that the base product, glucosamine, is really inexpensive – a fact that won’t be apparent as you start shopping; many of the products on the market are quite expensive. However, the most expensive supplements tend to be the combination products. Shop around and chose reasonably priced combination products if you think the added ingredients are appropriate for your dog, but look for pure glucosamine if prevention of joint deterioration is your goal. “The glucosamine is the important part of the compound,” asserts Dr. Bessent.
Although, ironically, it’s no guarantee, make sure the manufacturer provides a “guaranteed analysis” of the amount of glucosamine in each dosage.
The results of tests of glucosamine and glucosamine-combination products conducted by ConsumerLab.com, a firm that provides independent test results and information to help consumers and healthcare professionals evaluate health, wellness, and nutrition products, were released in November 2003. Of 49 products they tested, four contained much less chondroitin than the products’ “guaranteed analysis” stated. Shockingly, two pet supplements contained no chondroitin whatsoever – None! Zip! Zilch! – despite the labels claiming contents of 87.5 to 750 mg of chondroitin content.
Our recommendation is to look for a product with a guaranteed analysis, and then to contact the company and ask for proof of third-party testing or verification of the analysis.
In cases where dogs have medical conditions that preclude supplementation with glucosamine, chondroitin provides a treatment alternative. Most commonly, these conditions are as follows:
• Dogs having trouble with bleeding – Glucosamine may increase blood clotting times in dogs, so dogs with bleeding problems should not take glucosamine.
• Dogs diagnosed with diabetes or at risk for diabetes – Glucosamine is sugar-based and is not appropriate for diabetic animals.
Again, when choosing a chondroitin supplement, look for a product with a guaranteed analysis; then, contact the company and ask if they have third-party testing or verification of the analysis. This sort of reporting sounds extreme, but for a pricey supplement, given for a long time, it’s necessary to make sure you get your money’s worth.
Glucosamine Delivery and Dosage
There are several common delivery methods used for glucosamine supplementation: pills and capsules, powder, liquid, and intramuscular injection. Dr. Bessent deems all of these methods acceptable.
When an owner plans to use an oral glucosamine supplement, Dr. Bessent recommends a dosage level higher than she would use in an injection to accommodate some of the degradation that takes place in the dog’s stomach during digestion. Intramuscular injection gets the glucosamine into the bloodstream without traveling through the “acid pit” of the stomach, so she administers lower dosages of the injectable products. Pills and capsules that degrade properly in the stomach offer the same bioavailability as powders and liquids. Dr. Bessent recommends administering oral glucosamine supplements in the following daily dosages:
• Dogs 5-20 pounds: 250-500 mg
• Dogs 20-45 pounds: 500 mg
• Dogs 45-90 pounds: 1,000 mg
• Dogs more than 90 pounds: 1,500 mg
Use chondroitin supplements in the following daily dosages:
• Dogs less than 80 pounds: 900 mg
• Dogs more than 80 pounds: 1,800 mg
Dr. Bessent says she has been impressed recently with clinical results using d-acetyl glucosamine, a form of glucosamine given by injection. This supplement is not produced by pet supplement manufacturers and cannot be ordered from a catalog, but must be compounded by a veterinary pharmacist.
For many years Dr. Bessent has relied on Vita-Flex, an oral glucosamine supplement in powder form that she advises her clients to add to their horses’ and dogs’ food. For dog owners, check out the equine section of the Vita-Flex Web site, where the pricing is more attractive than for most “pet” supplements.
When determining the cost of glucosamine supplements, consider the following:
• Compare the cost per daily dosage of each product, not the cost per ounce or tablet. The milligrams of glucosamine per ounce or per pill vary by product, so calculate the cost of the appropriate daily dosage of each product for your dog’s weight to find the true cost of administering it.
• Make sure the dosage amount you must give your dog each day is reasonable. Some products require giving a large dog as many as eight capsules 2-3 times a day. Who wants to do that?
For Dash and her younger brother, I currently use Platinum Performance Plus as their daily, all-purpose supplement. A high quality wellness and performance product, the Plus formula adds a joint support component in the form of glucosamine sulfate at 500 mg per tablespoon.
Fifteen-pound Dash’s daily dose of Platinum Performance Plus (about two teaspoons) contains about 330 mg of glucosamine. I plan to either supplement this dosage with Vita-Flex to adjust her to the daily 500 mg level recommended by Dr. Bessent, or use the original Platinum Performance formula and add all of her glucosamine from Vita-Flex.
Lorie Long is a freelance writer and agility competitor from Virginia.