Can a drop of nicotine kill a person? The average lethal dose for humans is 0.5-5 mg/kg of body weight, i.e. at a weight of 70 kg, 35-70 mg would be lethal. One cigarette contains about 0.7-1.4 mg of nicotine. Thus, about 35-60 cigarettes can kill you if you smoke them one after another, although not all the nicotine from the cigarette enters the lungs, moreover, the toxic formaldehyde contained in tobacco deactivates nicotine. If we talk about drops, then one drop contains about 50 mg of nicotine, which means that one or two drops can kill a person.