What would cause a brown recluse spider to. Webjul 30, 2021 · spider bites are usually harmless, and spiders don't usually bite unless threatened. Spider bites can cause redness, pain and swelling, or you might not notice.

Webif the wound is untreated, it could lead to bruising, a blister, an open sore and scarring. A spider bite looks a lot like other bug bites, as well as some bacterial infections. It usually causes redness,. What does a spider bite look like?