I am jsut wondering this because my Rocky just absolutely hates it with a passion..at home...he is the most loveable, affectionate, sociable kitty, but as soon as we step into the vets office, there is a huge attitude change...I love the place he goes to..it is An all cats clinic...they only see cats and that's it...ok, well, First of all..Fluffy is an angel and always cooperates with no problem,..they always do her first....the last time,,I had to schedule him to be heavily sedated just for a check up...they had left him in his carrier and put the gas towards his carrier so it would relax him...enough to where they could get him out without him giving the doc a hard time...he bites at them normally, and has acheived before...anyway..they put the little gas mask on him and the entire checkup lasted 10 minutes at the most....then they put him back in the carrier, he was awake within 5 minutes after that on the way home having no clue as to what happened...(maybe he did,,I dunno)lol anyway..I hate to have to do this to him, but he gets super stressed out, won't relax, and the people at the vets office are so patient with him but deep down inside you can tell, it is quite aggrivating them..