Nicotine Facts

Nicotine is a naturally-occurring stimulant of the pyrrolidine alkaloid class. It activates acetylcholine receptors in the brain, triggering dopamine release in the brain's reward circuitry and producing its characteristic alertness and mood lift.

Subjective effects include increased alertness, improved sustained attention, mild mood elevation, and appetite suppression.^[1] In dependent users, the experience is dominated by withdrawal relief rather than positive reward — a quiet sharpening rather than euphoria.

Nicotine produces severe physical dependence — among the highest of any psychoactive substance — while its acute lethal dose is moderate at approximately 6.5–13 mg/kg orally.^[2] Tolerance builds within hours through receptor changes, and withdrawal peaks at 24–72 hours,^[3] locking users into a cycle of escalating use.