Have you eaten any chocolate or drunk any soda lately? If you have, there's a good chance you gave your body a dose of a stimulant -- caffeine, which is also in coffee. Eati…ng or drinking a large amount of caffeine can make you feel jittery, nervous, or energetic. That is because caffeine -- like any stimulant -- changes the way your brain works. But caffeine is just a mild example of a stimulant. Many other stimulant drugs are much stronger -- and some are illegal and very dangerous. Others require a doctor's prescription. Examples of stronger stimulants include: .
Cocaine: Made from the leaf of the coca plant, this drug often comes in the form of a white powder that some people inhale through their nose. .
Crack: A form of cocaine that can be smoked. .
Amphetamines: Often called "speed," these pills are sometimes prescribed by doctors for medical problems. .
Methamphetamine: A powerful form of amphetamine that comes in clear crystals (called "ice") or powder (called "crank") that is smoked or injected. (more about methamphetamine) From:www. counselingseattle.com ( Full Answer )