Because I'm "that" lady. I've read so many horror stories on here from vac reactions and I know benadryl can't hurt so I give it to her just in case. It's only $20 more and I just think I have more peace of mind getting it. She's perfectly fine after we leave the vet. She doesn't have any intense nervous reaction to the 2nd of the shots so I don't think it puts any undue stress on her. She'd be scared and pee on the 1st shot no matter if it's benadryl or the vac so I do it.
With that said...I am a firm believer in that the vacs are not needed every year (and I did the 3 year rabies) so she won't have to go thru this again for a very long time.
