I recently switched his feeds only a half scoop of grain daily and a half scoop of oats twice daily to lessen the sugar since he gets so hyper off of the grain, which I suspected to cause his rearing and he seems to have calmed a bit and doesn't rear or anything but now he is getting diarrhea or extremely soft and loose feces. I did an extremely gradual change, I did it over a two month period.
I also have him on Horseshoers secret hoof supplement for maintenance. What could be causing this? He has been wormed already, so I know its not worms nor the wormer causing this. He has been drinking and eating regularly. I'm nervous, and I don't know of anything to help sooth his diarrhea. His guts sound horrible and then he will defecate what appears to be water and very bright green feces and he's obviously uncomfortable. Before the diarrhea started, he was having rather foul smelling feces and when he passed gas it was extremely unpleasant, compared to his normal that is.
I can't get the vet out until next week because someone vandalized our car and I had to dip into my savings to take care of it on account I had to have the care repainted since they were so kind to spray paint it gold and break all our windows. I would rather self medicate if I can.