The LD50 of nicotine is 50 mg/kg for rats and 3 mg/kg for mice. 0.5-1.0 mg/kg can be a lethal dosage for adult humans, and 10 mg for children[2][4]. Nicotine therefore has a high toxicity in comparison to many other alkaloids such as ......., which in mice has an LD50 of 95.1 mg/kg. A person can overdose on nicotine through a combination of nicotine patches, nicotine gum, and/or tobacco smoking at the same time. [5][6] Spilling an extremely high concentration of nicotine onto the skin can result in intoxication or even death since nicotine readily passes into the bloodstream from dermal contact.[7]