I have an appendix/QH whose 9 yrs old, who can be great one mins, then excitable super reactive to good and bad things around. for the most part he is pretty good. but on the trail he looks around gets nervous/ excited when he sees other horses on the trail or noises... its random... he'll spook in place sometimes backing up a step or two.. .I was thinking about buying earplugs... has anyone used this on their horses ? and how did it work? wha about supplements... there are so many, Im looking for something with no long term effects. Im not looking for a cure, but something to take the edge off and foucs on me more , than something else on the trail that gets him nervous or excitable. I also noticed if there is alot going on he gets nervous, like its all to much to take in.... sensory overload. like today there wwere riders up the street comming and damn small dogs barking., and the White STOP letters in the street, made him get all funky.... any suggestions. I do ground work and desensitizing with him all the time... and hes pretty good, he jsut gets these random spooks or nerves going. due to him being Appendix. 
thanks in advance!
everyone here has provided me great answers. as it is now I have ponied him with another TB horse and he did good. but as of right now Im walking him on the line out on trail and he shows alot of nerves or excitability when he sees something like tarps blowing in the wind, the craxy thing is I work with tarps on him at home and hes great, but taken on trail with tarps, he lifts his head and sniffs. and walks sideways from them, I dont get it. I allow him to face the object, he has never bolted or ran, but when he lifts his head and smells etc, it makes me wonder if he's thinking of bolting... he just seems like the type that super sensitive to react the way he lifts his head and focus attention on other things except me. Im going to try to learn to disengage the hips more. if I could give you all pts I would. all of you have been helpful!!! thanks so much
thanks in advance!everyone here has provided me great answers. as it is now I have ponied him with another TB horse and he did good. but as of right now Im walking him on the line out on trail and he shows alot of nerves or excitability when he sees something like tarps blowing in the wind, the craxy thing is I work with tarps on him at home and hes great, but taken on trail with tarps, he lifts his head and sniffs. and walks sideways from them, I dont get it. I allow him to face the object, he has never bolted or ran, but when he lifts his head and smells etc, it makes me wonder if he's thinking of bolting... he just seems like the type that super sensitive to react the way he lifts his head and focus attention on other things except me. Im going to try to learn to disengage the hips more. if I could give you all pts I would. all of you have been helpful!!! thanks so much