兴奋剂是一种精神药物，它可暂时改善生理或心理功能，例如增强的警觉性，清醒度，运动功能。镇静剂(depressants) 为功能相反的药物。 兴奋剂在全世界被广泛使用，作为处方药或非处方的合法或非法娱乐性药物。

医学导航：心理学／精神病学

心理历程

障碍（o, p, m, p, a, d, s）
症状／齐名／涉及

操作（评估／治疗）
药物（N5A/5B/5C/6A/6B/6D）

Stimulants (also referred to as psychostimulants) are psychoactive drugs that induce temporary improvements in either mental or physical functions or both. Examples of these kinds of effects may include enhanced alertness, wakefulness, and locomotion, among others. Due to their rendering a characteristic "up" feeling, stimulants are also occasionally referred to as "uppers". Depressants or "downers", which decrease mental and/or physical function, are in stark contrast to stimulants and are considered to be the functionally opposite drug class. Stimulants are widely used throughout the world as prescription medicines and without prescription both as legal substances and illicit substances of recreational use or abuse.