A psychoactive drug is a drug that has an effect on your mind — how you feel, think, sleep, or see things. It acts on the brain. Coffee is a little psychoactive, because caffeine wakes you up. Alcohol is psychoactive. Some hospital medicines are too, on purpose, to help with pain, fear, or low mood. Illegal drugs that make people high are also psychoactive. The word does not mean “mad,” and it does not mean “illegal.” It only means “it changes the mind.” Scientists, doctors, and news reports about drugs use it. In the street, people are more likely to say the drug’s name.