Equine reactivity is a major problem for some riders. Reactive horses are more likely to spook, bolt, or become hard to handle. Some reactivity is hard wired into the horse's survival instinct while some is an overreaction to an everyday stimulus. The first thing to do when you suspect your horse is reactive is to rule out any pain. Get the vet out, have the saddle fitter out, and check your bridle fit. When pain is ruled out as the cause, things become more difficult to manage. Some riders work well with reactive horses, others do not. There are calming supplements that can help take the edge off reactivity if your horse is still reactive after pain has been ruled out.