Pet spas offer "paw-dicures"; celebrity chefs dish up treats at pet delis; and everything from braces to stem cell transplants to heart surgery is now available for your pet... assuming you can afford it. The newest trend is the most controversial and revealing: psychoactive drugs for dogs and cats. Identifying a multi-billion dollar untapped market, Big Pharma has just released a handful of designer drugs for pets, treating aggression, separation anxiety, obesity, and diminished mental capacity due to aging, with more medications to follow.