Nicotiana tabacum (Cultivated Tobacco)
Tobacco can be used to treat bee stings. First, if still present, remove the stinger. Then mash the tobacco leaves and rub directly onto the sting, the nicotine will act as an anesthetic, and the pain should go away after a few minutes.
While the tobacco plant works best, you can also use cigarette tobacco in a pinch.
Unroll a cigarette and add a bit of warm water to the tobacco so that it becomes moist. Next mash the wet tobacco until you see the juice running out. Finally apply the tobacco to the area of the sting and let sit for 15 minutes or until the pain subsides.