Calming supplement

I have been training my horse dressage for the past 5 years and jumping for 7, but over the past 3 years or so, he's been getting more spooky and agressive. The vet seems to think that when he was castrated there was some tissue left behind that still produces testosterone. We are trying him on Regumate to see if that helps, but so far...no! Oh, and the vet said he was in great health otherwise, eyes are fine, etc. I am looking at calming supplements and I don't know what to think. I've never used them in my 10 years of riding and not sure what other peoples experiences are. My mom and I have been riding him for years and when he spooks he bolts. We are fine with him bucking, but it's the bolting that scares us most. We don't fall off usually, but it's not fun!

If I was you I would use chamamile, it is a great calming herb. But you can buy pastes and stuff but I would rather feed herbs then chemicals

Vitamin B1 (thiamine) is good for claming. It comes as a powder or paste and as its completely natural it wont show up on drug tests at shows.

I used herbal mix (raspberry leave, chamomile, and so on) and it didn't help at all on my nervous horse. Calm&cool helped a little, but not whole a lot. I think it depends on horse a lot.

Magic Mare or Moody Mare. Yes, it can be used on a gelding too

How's his diet? Lot's of sugars/carbs? (I'm sure you know, since you've been in horses a while...but my first thought was SuGaR BuZz!)

I've used Calm'Em (Thia Cal) and it worked great.

I have used Calm & Cool its seemed to work on my horse :)