Ok there are 20 000 different spiders in north america. Only 60 of em bite. But only 4 of the 60 spiders are poisenous. THey are the yellow sac spider, the aggresive house spider, the black widow spider, and last but not leats the recluse spider which has a very nasty bite. If you get bit by a non toxic spider there will be a bump sometimes the bump is itchy. Don't ITCH IT. But since it is not poisenous nothing will happen other than the bump. If you get bit by a poisen ous spider you will feel heat. It is not red a;ll the time.if you feel different or the bite is VERY painful get to hospital immediatly as th blak widow and recluse spider bites can kill with a matter of very short time.
If poison it gets red has heat and starts to rot where the poison is get to hospital immediately to get antidote