We have a 16 year old Thoroughbred broodmare who has always been a bit alpha female, but last year 4 trips to the stallion failed to get her in foal. When she came home she was irritable and started to kick holes in the stable and field shelter walls, as well as the occasional field companion and for no apparent reason. After one screaming match in the paddock at 10pm, I decided something had to be done and wondered if was down to hormone imbalance. I asked my vet if I could put the mare on Ritalin for a month to see if it would help. The effect was immediate and she became docile and calm once more and has been that way ever since. I am now about to put her in foal again and am wondering if this is going to upset the applecart and if anyone else has similar experiences with broodmares and advice to share.