Cosequin Optimized contains higher levels of active ingredients, now with glucosamine hydrochloride at 14,400 mg and with 2,400 mg of chondroitin sulfate (per 2 scoops), as compared to the original researched formula and is formulated as a tasty powder. The increased amounts of ingredients in Cosequin Optimized stem from current opinion suggesting that high activity horses may benefit from higher levels of glucosamine. Cosequin Optimized with MSM has the same levels of active ingredients as Cosequin Optimized but has the further addition of high purity MSM, or methylsulfonylmethane. MSM is an organic source of sulfur, a compound used by cartilage. Some veterinarians suggest using MSM to help manage joint health. Cosequin Optimized with MSM for horses contains 10,000 mg MSM (per 2 scoops). For those wishing to additionally supplement MSM, Cosequin Optimized with MSM offers a convenient, cost-effective way to administer MSM along with the proven ingredients in Cosequin. Cosequin Optimized with MSM: Each 16.5 Grams (1 Level Scoop) Contain: Manganese minimum.32mgGlucosamine Hydrochloride minimum.7,200mgMethylsulfonylmethane (MSM) minimum.5,000mgSodium Chondroitin Sulfate minimum.1,200mgCosequin Optimized with MSM contains FCHG49 Glucosamine and TRH122 Sodium Chondroitin Sulfate, Nutramax Laboratories proprietary veterinary researched specifications.