My mare has started developing alley issues. Last race she blew off the pattern. Her gate issues have gotten steadily worse but blowing off the pattern is a new thing. She's always been so consistent and honest once in the arena. She's not underweight. She has had allergies flair you 2 years ago at her previous home but hasn't happened in her new environment. She trail rides with no issues. She is cinchy and I have to slowly cinch her or she'll fly backwards. She also sometimes looks back at her stomach when I'm on her if she's getting anxious before a run. But again she's not underweight like a typical ulcer prone horse. She's actually slightly overweight if anything. She also likes to fly backwards at any reason and can't be tied to the trailer for this reason (has broke many a halter and still reacts even with a special hook for this type behavior). I am starting gastrogard to treat for ulcers. But I'm wondering if I should have her checked for bleeding. What does the test for bleeding involve? I've given her about a month off from racing will a test still be able to find out if she's a bleeder? What is the general treatment plan? Once resolved what is the preventive measures? I've heard of lasix but I'm not familiar with it. Is this the only effective treatment/preventive? How do you get it, vet only? Thanks in advance for all your help! 

To determine if bleeding you have to scope 24-48 hours after the bleed. Unless she's got a ton of scarring they won't be able to see anything. I've also never seen a horse with ulcers that isn't still in great weight with a shiny coat. They've all looked healthy as heck and been full of them. If she's that cinchy, thats where I would start. Make sure you add a daily prevention with the GastroGard or when you pull her off the treatment her body will overproduce acid and most likely flare them right back up. They're called rebound ulcers and you have to go through the whole treatment again. It could also be a combo of ulcers and bleeding. Coordinate with you vet to where you can scope the day after you run, they can also check the gut while they're doing it. If she is bleeding you'll have to run on lasix, which is no big deal and very cheap