I've seen more adverse reactions to metacam than to rimadyl.
Bear in mind, that although you won't be charged for the prescription, you may be charged for the initial examination, or "medicines determination fee". We're not allowed to prescribe POM-V's for an animal without having a knowledge of that animal (so don't get pissed off when you ask or a prescription for something, and are told that you can't have one without the animal being examined)
Jim