I use Vita-Calm about once a week in some apple sauce....my mare loves it! But, she is a food hog anyway, lol. Plus, she is pacing or anxious when I put her back into her stall after a workout. She waits and talks to me till she is put out into the pasture.
Check under your mare's abdomen to see if she has any skin issues. I noticed a sore on mine when I first bought her, and the bo said it was nothing, got a little better after worming, but, the vet at my new barn said to use Ivermectin. Did some research and the skin issue appeared siminilar to Neck Threadworms. Treated her with Ivermectin and the skin has cleared up. My mare will usually turn her head towards me whenever she is in season and cramping while tacking up. The Vita-Calm really helps her feel better and we have a much better riding session afterwards. I don't want to give it to her every day because it builds up in their system and then you have to be off it for two weeks. So, I just give it to her either once a week or every two weeks to help.