Thank you for the shout out. Gastroplus is pretty great stuff. Any feed through can take a bit to show results. The great thing about this product is it helps produce the mucous lining the stomach needs to protect against the acid. It's not just a cover up.

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I have an ulcerous gelding and I was not satisfied with the omeprazole/sucralfate regime he was on per vet. Nor the cost. Put him on 3 generic Esomeprazole pills a day and have been very pleased with the results all last year. Vet said if it's working, keep using them. 

Lots of ideas here, and some different takes on treating ulcers. Here is my 2 cents. Treating is a multi step process. One step is treating existing ulcers, the second is finding the reason that they are there in the first place. The third is modifying the management of the diet so that they do no return when treatment is over.

You already are addressing number 1, but I agree that the feeding schedule is wrong. Do not feed for an hour after treatment, but have roughage available at all times after. If there is no alfalfa in the diet, this is a good time to add some. The added calcium and low starch and sugar of alfalfa can be a benefit. Eliminate all grain based feed in the diet. 

Be sure teeth are up to date. This is the most often missed issue with ulcer horses. A horse only makes saliva when it chews. This is the natural buffer for stomach acid, and one reason that roughage should always be available to cause that saliva to be produced. If the horses mouth hurts to chew, it will only chew enough to swallow and as a result little saliva will be produced. The ratio of food material, saliva and stomach acid will then be out of balance and ulcers can result. If you don't fix the teeth, the ulcers will return as soon as your treatment is over.

Hope this helps. 

I think you said you had some pros fit the saddle but that sounds like it could be a saddle-fitting problem. You said: "His only symptom is decreased peformance under saddle - he has a very poor attitude, swishes his tail, pins his ears, reluctant to stride out and is just overall not happy to be ridden." Any issues when lunging him? Could you try a treeless saddle on him? 

THIS^^^^^  Forage is sooooo key!  Keep something in front of them all day and night.

My mare got badd ulcers when we started upping her grain and had the vet prescribe her omeprazole for a month. The omeprazole did not work and she only got worse until a friend suggested an ulternative. We put her on camelina oil (which is wayyyy cheaper btw) and saw results in less than a week. Most feed stores should have it. It also really helps with joint issues and other general wellbeing.

You should be seeing positive results.  I'd take a serious look at EPM!  It is one nasty bug that hides behind so many different symptoms that create behavior issues.  

Mine went off alfalfa before she was treated for ulcers. She would eat grass hay all day. I've heard of other that do this. Alfalfa always has more stems. 

You said with "no food in between"  that may be your problem.  Alfalfa is the best thing for ulcers and helps keep the gastric acid down.  horses are meant to be grazers do your research on this.  My very hot mare had grade 3 ulcers and i keep her on all the alfalfa she wants and turn out and when we go to a show she has alfalfa in front of her always.  she has not had issues since.  also I use Abler paste(same as ulcerguard/gastroguard) as a proactive and 3-4 days before a race I give a full tube everyday.  Abler is from Austraila and has been a life saver for me.  its the exact ingredients as gastroguard only $10 a tube.  You need to make sure your not using a compounding omeprazole only use either gastroguard/ulcerguard or Abler paste every day for 30 days and I bet things change. 

Could you tell me which one you are using?

You can find research that concludes gastric ulcer get better on alfalfa, and you can find research that says gastric ulcers worse on alfalfa diet. Find what works on your horse.