BTW, if anyone stumbles across this forum and is giving their dog allergy shots, I would HIGHLY recommend this little gadget -
Amazon.com: Autoject 2 Self-injection Device... . It automatically sticks the needle in and injects the serum, virtually painlessly! (I know because I tested it on myself first). Giving shots to dogs is REALLY hard, especially when you're doing it every other day. This little device makes it a breeze.