My apologies if this has been discussed. I did a search and found threads discussing each of these separately, but no comparisons of the two.
A little background. My then 7 yr. old gelding came up slightly lame in the LH fetlock in September 2011. X-rays were clean, vet recommended a course of Adequan at the loading dose. We did 7 injections, 4 days apart and by injection 3 he was sound and moving exceptionally well. After the loading dose, I continued with one injection every 4-6 weeks. Fast forward to this past August. Once again just very slightly off on the LH fetlock (less so than in 2011) and vet recommended injecting the joint. Went ahead with joint injection and again my boy is moving like a million bucks and continues to do so, with no Adequan or any other joint supplement at all.
Just recently, I have heard a little about Pentosan vs. Adequan. I am sure I will go back to using an injectable joint supplement at some point and am interested in hearing your experiences with Pentosan, especially if you also have experience with Adequan.
ETA: My gelding is a dressage horse, currently showing at third level, schooling above.
I have used both and although I did see some results with Adequan I would not say they were nearly as impressive as the results I have had with Pentosan.
In addition, if your vet will write you a script to Wedgewood it is much more cost effective to use Pentosan. A 50ml bottle of Pentosan from Wedgewood is around 120.00 (that is 8, 6ml doses) whereas a 7 shot series of Adequan will run you about 280.00.
Pentosan is labeled for a series of 4 once a week IM shots as the loading dose and also labeled for use as needed thereafter (some people do twice monthly, others do once a month).
In comparison, Adequan is only labeled for the 7 shot loading dose. There are vets that prescribe the once monthly shot thereafter but that is "off label" and there is no evidence that Adequan is effective when used in that manner.
I used Adequan for my horse when he was 18/19ish before I started injecting his hocks. I saw some improvement for a short period but ended up having to inject his hocks shortly thereafter. He is now 21 and gets once a year hock injections and also gets Pentosan once a month. I noticed a huge improvement after the Pentosan loading dose and continue to notice improvement after he gets his monthly shot. He is in regular work 5-6 days a week and jumps 2'6ish once or twice a week. The Pentosan keeps him limber and comfortable.