Cosequin ASU wins this comparison 6.5 to 5.9, and the gap is entirely about what gets added on top of the identical base formula.
The deciding factor is Dosing Adequacy (12/20 vs 8/20). ASU adds 1,050 mg of avocado/soybean unsaponifiables at full research-protocol threshold plus 300 mg of boswellia. That fourth scoring slot pushes ASU over the badge line; the Optimized version sits below it without those additions.
Cosequin Optimized MSM has one real advantage: it costs $0.29/day less ($1.44 vs $1.73) for the same base formula and the same Nutramax pharma-grade manufacturing.
If your horse has early cartilage changes on imaging, a joint history that warrants anti-inflammatory support, or your vet recommended ASU specifically, Cosequin ASU is the buy. It’s the only product in our Joint Health database with full-dose ASU and the Recommended badge.
Skip the ASU version only if your horse’s joints are sound and you want the Nutramax QC platform at the lowest entry price. $0.29/day over 365 days is $106, and for a preventive-use horse that’s real money.
Full audit reports linked at the bottom of this page.
The Scores
| Cosequin ASU | Cosequin Optimized MSM | |
|---|---|---|
| Overall | 6.5 | 5.9 |
| Label Transparency | 12 / 15 | 12 / 15 |
| Ingredient Form | 15 / 20 | 14 / 20 |
| Dosing Adequacy | 12 / 20 | 8 / 20 |
| Formula Design | 10 / 15 | 7 / 15 |
| Quality Assurance | 6 / 15 | 6 / 15 |
| Value | 10 / 15 | 12 / 15 |
| Badge | Recommended | — |
| Cost/day | $1.73 | $1.44 |
In our 15-product Joint Health database, Cosequin ASU ranks #3 overall (Recommended) and Cosequin Optimized MSM ranks #7 (no badge). Both carry QA = 6/15, tied with each other and higher than every non-Nutramax product in the category. This is the cleanest ingredient-for-ingredient comparison in our database: same manufacturer, same QC platform, same glucosamine source, different formulation additions.
ASU and Boswellia — The Extras That Change the Product
Strip away the additions and these are the same supplement. Both deliver Nutramax’s FCHG49 glucosamine at 7,200 mg (72% of the 10,000 mg threshold), 5,000 mg MSM (50%), and 1,200 mg chondroitin sulfate as TRH122 (48%). Same serving size, same trademarked specs, same batch-level QC.
The gap opens at the fourth scoring slot. Our Dosing Adequacy rubric scores four ingredients: glucosamine, MSM, chondroitin, and then either HA or ASU (whichever the product delivers). Cosequin ASU delivers 1,050 mg of avocado/soybean unsaponifiables — 105% of the 1,000 mg research threshold, scoring 4/4. The Optimized version has no HA and no ASU, so that fourth slot scores 0/4. Four points gone.
Boswellia at 300 mg adds anti-inflammatory support from a separate pathway. Manganese at 250 mg (versus 32 mg in the Optimized version) is a cartilage cofactor at a meaningful dose. Together, these additions push Formula Design from 7/15 to 10/15.
The result: ASU scores 12/20 on Dosing Adequacy, just above the 12-point threshold required for the Recommended badge. Optimized MSM scores 8/20, not close enough. That DA gap, combined with the 3-point Formula Design advantage, produces the 0.6-point total score difference despite identical base ingredients.
Why ASU at 1,050 mg actually matters, not just on paper. Avocado/soybean unsaponifiables work through a different mechanism than glucosamine or MSM: rather than providing substrate for cartilage synthesis, ASU appears to inhibit the enzymes that drive cartilage breakdown (Henrotin et al., 2003). That’s a pathway the Optimized version leaves entirely untouched. For a horse with early osteoarthritic changes on imaging, the ASU mechanism isn’t redundant with glucosamine; it’s complementary. The 4-point rubric score gap translates to a real biochemical difference you can point to, not a documentation technicality.
Why the gap changes the buying decision more than the scores suggest. Within the Cosequin line, Optimized exists as a budget option for owners who want Nutramax quality without paying the ASU premium. That framing is accurate for preventive use, misleading for therapeutic use. A horse without joint concerns probably does fine on the base formula; an 18-year-old performance horse with a history of hock injections does not. The ASU isn’t an upgrade; it’s what separates a maintenance product from one addressing an active condition. Buying Optimized for a horse that actually needs ASU saves $0.29/day and loses the only ingredient in the formula that addresses the horse’s specific pathology.
Cosequin ASU is the only product in our 15-product Joint Health database that delivers ASU at or above the 1,000 mg research threshold within a Recommended-badge product. Platinum CJ has more ASU (2,000 mg) but fails on Value at $6.17/day. For full-dose ASU at a reasonable cost, ASU stands alone in the category.
Where the Optimized Version’s $0.29 Savings Earn Their Keep
Cosequin Optimized costs $1.44/day from the 1400 g container. Cosequin ASU costs $1.73/day. The Optimized version scores 12/15 on Value versus ASU’s 10/15. Over a year, feeding one horse, that’s $106 saved. For two horses, $212.
The quality platform is identical. Same QA score (6/15, tied for the highest in our database), same Nutramax manufacturing discipline, same trademarked specs, same public batch documentation. Whether you buy ASU or Optimized, the paper trail is the same. For a horse with no existing joint issues and a handler who wants pharma-grade basics at the best price in the Nutramax line, the Optimized version is a reasonable choice.
Cosequin Optimized MSM’s 12/15 Value is the highest among products in our Joint Health database that share Nutramax’s pharma-grade QC platform. You’re paying for the Nutramax quality standard without the ASU premium. That’s a valid trade for a preventive-use horse, a weak trade for one with active joint concerns.
What’s in Each Scoop
| Ingredient | Cosequin ASU | Cosequin Optimized MSM | Threshold |
|---|---|---|---|
| Glucosamine HCl (FCHG49) | 7,200 mg | 7,200 mg | 10,000 mg |
| MSM (NMX1000) | 5,000 mg | 5,000 mg | 10,000 mg |
| Chondroitin sulfate (TRH122) | 1,200 mg | 1,200 mg | 2,500 mg |
| ASU | 1,050 mg | — | 1,000 mg |
| Boswellia extract | 300 mg | — | — |
| Manganese | 250 mg | 32 mg | — |
| Serving size | 17.5 g | 17.5 g (pellet) / 16.5 g (powder) | — |
| Cost/day | $1.73 | $1.44 |
Which One for Your Horse
Buy Cosequin ASU if: your horse has early cartilage changes visible on imaging, a joint injection history requiring ongoing protection, active stiffness under saddle, or your vet recommended ASU specifically for its anti-inflammatory mechanism. The ASU dose works through a pathway glucosamine can’t reach. For $0.29/day more, you get the Recommended badge, full-threshold ASU, and boswellia on top. This is most horses with a known joint issue.
Buy Cosequin Optimized MSM only if: your horse has no current joint concerns, you’re feeding for preventive maintenance, and you specifically want the Nutramax QC platform at the lowest price point in the product line. You lose ASU and boswellia, and with them the Recommended badge, but the core glucosamine-MSM-chondroitin stack is identical to the ASU version.
For a horse with any active joint concerns, Cosequin ASU is the buy.
Frequently Asked Questions
Why doesn’t Cosequin Optimized MSM earn a Recommended badge?
The Recommended badge requires a total score ≥ 65 AND a Dosing Adequacy score ≥ 12. Cosequin Optimized scores 59 total and 8/20 on DA, missing both thresholds. Without ASU filling the fourth scoring slot, three of its four scored ingredients fall below therapeutic levels. The base glucosamine-MSM-chondroitin stack alone isn’t enough under our scoring rules, regardless of how well manufactured it is.
Can I just add a standalone ASU supplement to the Optimized version?
In theory yes. In practice standalone equine ASU products are rare and expensive. Most ASU reaches horses as part of combination products like Cosequin ASU itself. If you buy ASU separately, you’ll likely spend more than the $0.29/day difference by the time you source a quality standalone. Simpler path: just buy the ASU version.
I’m already using Cosequin Optimized MSM. Should I switch?
If your horse shows any joint symptoms (stiffness on first steps, occasional short-striding, visible hock soreness), switch to the ASU version. The $0.29/day extra is the cheapest path to full-threshold ASU in our database. If your horse is sound and you’re on Optimized for general wellness, stay put.
Sources
- Full audit report: Cosequin ASU — complete scoring calculations, label analysis, and sources.
- Full audit report: Cosequin Optimized MSM — complete scoring calculations, label analysis, and sources.
- Henrotin YE, Sanchez C, Deberg MA, et al. Avocado/soybean unsaponifiables increase aggrecan synthesis and reduce catabolic and proinflammatory mediator production by human osteoarthritic chondrocytes. J Rheumatol. 2003;30(8):1825-1834. PubMed ID: 12913942. Mechanism evidence for ASU at 1,000 mg dose.
- Kimmatkar N, Thawani V, Hingorani L, Khiyani R. Efficacy and tolerability of Boswellia serrata extract in treatment of osteoarthritis of knee — a randomized double blind placebo controlled trial. Phytomedicine. 2003;10(1):3-7. PubMed ID: 12622457. Boswellia mechanism and dose-response data.
- Nutramax Laboratories Veterinary Sciences. Cosequin ASU and Cosequin Optimized MSM product documentation — FCHG49, TRH122, NMX1000 trademark specifications. cosequin.com/equine. Accessed April 2026.
- EquineAuditLab Methodology. Badge system hierarchy and Dosing Adequacy thresholds. /methodology/. Explains the DA ≥ 12 + total ≥ 65 criteria for the Recommended badge.
Read the full audits: Cosequin ASU (6.5) | Cosequin Optimized MSM (5.9)