Nicotine Drug Test. In order to know the fact as to how long nicotine stays in your system, you need to remember the duration of smoking and the number of cigarettes smoked per day. Usually nicotine persists in the body for 2-4 days but in some cases it may also last for a few months. However, in the case of passive smoking the nicotine remains in the body for a long time. The presence of nicotine is usually detected in the urine, blood, and hair follicle through medical tests.