Nicotine regulation and cigarette smoking.

A study was conducted to determine whether there is nicotine regulation in cigarette smoking. Tar levels, which often covary with nicotine manipulations, were controlled for by the use of nicotine in chewing gums. Nicotine in cigarettes was also used for preloading. High nicotine cigarette preloads were followed by longer latencies to the next cigarette than were the low nicotine cigarette preloads. High nicotine gum preloads were followed by less puffing on the subsequent cigarettes than were the low nicotine gum preloads.