This species is slightly more aggressive than most house spiders and will bite, perhaps repeatedly, if threatened. Most contact with yellow sac spiders is accidental for its part. They tend to hide in piles of clothes (clean or dirty) and bite if they feel pressure when the clothes are picked up and/or put on.
There is no consensus on how toxic the bite of this spider may be, although it is not known to be deadly. The initial bite can be painful to some people, but unnoticed by others. For some, a small red bump will form and eventually fade after a couple of weeks. In others, swelling, burning and pain are experienced the first hour or so after the bite, then a pustule develops that naturally heals over a couple of weeks. If bitten, it is suggested that the spider is caught (not smashed) so it can be identified if the bite develops into a serious skin infection. Contact your physician if it appears this spider's bite is growing worse.