Sometimes works. Usually doesn’t. If the irritant is injected deep, the way that a mosquito does, this thing’s not going to draw it out before it becomes embedded in the tissue. But for a bee sting on the palm of your hand, where the bee didn’t leave the stinger behind and the skin is thick and relatively tough, you’ve got a good chance of it working. You’ve also got a good chance that just by sucking on it yourself, you would achieve the same thing. In any event, once the welt from the sting forms, it’s much too late for this to do anything. You basically have to apply it immediately after the bug leaves or has just been smashed. Which runs into the problem of remembering where the hell you left it. Yeah, not going to happen.