A substance that causes partial or total loss of sensation (e.g. pain), with or without the loss of consciousness.
A temporary or complete loss of vision, consciousness, or memory.
A substance that slows down the function of the central nervous system. Depressants are known to calm you down and relax your muscles; therefore, your breathing and heart rate decreases when you take a depressant.
A spontaneous and involuntary recurrence of a specific experience that originally occurred while using a drug. Flashbacks are usually associated with hallucinogenic drugs and can occur days, months or years after the drug has been taken. There is no way to control a flashback.
A drug that affects your mood, thoughts, and perceptions. Hallucinogens can cause you to see, hear, or feel things that are not real - commonly referred to as hallucinations.
A condition in which the presence of a drug is required to maintain a normal functioning of the central nervous system. A person can experience withdrawal symptoms if they don't get their drug "fix".
The strong desire to continue taking drugs to produce the effects experienced when on the drug. The drug becomes so important to the user that it can be difficult to stop using it or even thinking about it.
A substance that has a soothing, calming, or tranquilizing effect. In large doses, sedatives induce sleep and unconsciousness .
A substance that speeds up the central nervous system giving the user a sense of excitement. Can make the user very alert and aware of things around him/her. Nicotine and caffeine are stimulants .
A condition in which higher doses of a drug are required to produce the same effect as experienced initially. The user needs more to feel the same "high".