I worked in the Texas prison system and can assure you that using Chemical agents will almost certainly zap you, too! Being hit with a chemical agent will ruin your defense and/or escape! Deranged or mental Offenders eat the stuff and it has virtually NO stopping effect on them.
I rode my bicycles 3,414 miles in 2011 and was attacked by dogs on several occasions. One dog bit me and I called the county Sheriffs Deputies to file a complaint. They TOLD me to carry an ASP baton. I questioned that saying that I heard they were against the law to carry. They said no. I have my CHL but I'm not going to shoot some kid's dog. Besides, it is said that each round in your carry pistol has a $20,000 price tag on it. I'm not going to open that can of worms! I now have a 26" ASP affixed to each one of my bikes.
When my dog Jake and I walk, I carry a CaneMaster martial arts cane. I studied the techniques and the darned canes are brutal!
I will expend every option before I use my carry gun. If I can neutralize an attacker without shooting him/her, I will do that.