Joint Health Supplements for Pets Review (Glucosamine, Chondroitin, MSM & Boswellia)
Initial Posting: 9/29/2018
(See Separate Review of Joint Health Supplements for People >>)
- Do they help? Based on preliminary evidence, glucosamine and chondroitin may help reduce symptoms of degenerative joint disease in dogs and cats. Boswellia may also help, as an anti-inflammatory. MSM may help with muscle soreness. (See What It Does).
- What did CL's test find? One product contained only about three-quarters of its listed glucosamine and chondroitin and it was not possible to test another.
- Which product is best? Products that passed CL's tests of quality are noted as "Approved" in the Results Table below, where they are also compared. Approved products which also provided high-quality ingredients at lowest cost — indicating superior value — are noted in the last column of that table. Among these, CL selected a Top Picks for Dogs and a Top Picks for Cats.
How much to give your pet?
Dosage for these each of these ingredients should be adjusted depending on the weight of your pet (see Dosage in the ConsumerTips).
- Glucosamine and chondroitin: These may be used separately, but most supplements contain a combination. For a 25 lb. pet, a typical daily dose is 500 mg glucosamine hydrochloride and 400 mg chondroitin sulfate.
- MSM: An optimal dose has not been established.
- Boswellia: In dogs, 400 mg of Boswellia extract per 10 kg body weight (22 lbs.) has been shown to reduce joint pain and stiffness. Taking Boswellia extract along with fatty foods may enhance absorption. Note that if only Boswellia resin is listed, it is likely less potent than Boswellia extract, and extracts can vary in AKBA (a boswellic acid) concentration from about 2% to 40% -- although the amount of AKBA is rarely listed on labels.
- Cautions: Most of these ingredients can cause some gastrointestinal upset, such as nausea and diarrhea and, although generally safe, some can interact with drugs, trigger allergies, or cause other side-effects. MSM may have an aspirin-like effect and shouldn't be used by pets already taking blood-thinning drugs, unless medically supervised (see Concerns and Cautions).
What It Is:
Glucosamine and Chondroitin:
Glucosamine and chondroitin sulfate occur naturally in the body. The glucosamine used in supplements is typically derived from the shells of shrimp or crabs although a corn source is also available and becoming more prevalent in the market. Glucosamine is available in a variety of chemical forms, such as glucosamine hydrochloride and glucosamine sulfate. These vary in terms of the amount of actual glucosamine available for use in the body from an equal weight of each form (See ConsumerTips™ for Glucosamine for more information). Chondroitin sulfate is generally derived from pig and cow cartilage, but even shark and chicken cartilage have been used. Chondroitin-like mucopolysaccharides from algae are also available.
MSM (methylsulfonylmethane) occurs naturally in the body but MSM in supplements is produced synthetically.
The gum resin of the Indian frankincense tree (Boswellia serrata) contains compounds (boswellic acids) thought to have anti-inflammatory properties. Most supplements contain an extract of this resin, often standardized to contain specific amounts of one or more of these boswellic acids, such as AKBA.
What It Does:
Glucosamine and Chondroitin:
Glucosamine and chondroitin sulfate supplements are used to slow the progression of osteoarthritis (also referred to as degenerative joint disease or DJD) — the deterioration of cartilage between joint bones common in older dogs and cats as well as in horses. They may also reduce associated pain. Clinical signs in animals may initially include stiffness, difficulty rising, and reluctance to exercise and progress to loss of joint range of motion, lameness, and muscle loss.
Glucosamine is thought to promote the formation and repair of cartilage. Chondroitin is believed to promote water retention and elasticity in cartilage and inhibit enzymes that break down cartilage.
Most of the clinical research on glucosamine and chondroitin has been conducted in humans (see separate report on Joint Supplements for people) which has found that the combination of glucosamine and chondroitin sulfate seems to be effective in osteoarthritis patients with moderate to severe knee pain, but not those with mild pain — although not all studies show benefit.
Animal studies have been limited. However, in experimental models of osteoarthritis in small animals, such as dogs, both preventative and therapeutic benefits have been seen. Results in horses have been more variable. One study in horses with osteoarthritis showed improvement in lameness, flexion, and stride length within two weeks of treatment with glucosamine, chondroitin and manganese, although there were no further improvements after four weeks. Results of other studies using this combination have varied. As summarized in a 2005 article in the Journal of the American Veterinary Medical Association (Neil, J Am Vet Med Assoc 2005), "Results of clinical trials of glucosamine and chondroitin sulfate in horses suggest possible improvement in clinical signs; however, rigorously designed long-term trials are needed."