Drug GK

What is a drug?

A drug is any substance—solid, liquid or gas—that brings about physical and/or psychological changes in the body. 


Psychoactive drugs affect the central nervous system (CNS). They act on the brain and can change the way a person thinks, feels or behaves.

Some drugs, such as alcohol, caffeine, nicotine and various prescribed and over-the-counter medications, are legal. Most legal drugs are restricted and their availability, quality and price strictly controlled.




Other drugs, such as cannabis, methamphetamines, ecstasy, cocaine and heroin, are illegal. They are not subject to quality or price controls. This means that a person can never be sure of the drug's strength or what is in it. Different batches of an illegally manufactured drug may have different concentrations of the drug and other additives. Sometimes, the additives can be poisonous. Even the drug itself could be poisonous.

Types of drugs and their effects

Drugs can be classified according to the effect they have on the CNS—and the way they change how a person thinks, feels or behaves. The three major classifications are depressants, stimulants and hallucinogens.

Depressants

Depressant drugs don't necessarily make a person feel depressed. They slow down the functions of the CNS and the messages going between the brain and the body. Depressants affect concentration and coordination. They slow down a person's ability to respond to unexpected situations.
In small quantities they can cause a person to feel more relaxed and less inhibited. In larger quantities they may cause unconsciousness, vomiting and, in some cases, death.
Depressant drugs include:

• alcohol
• barbiturates
• benzodiazepines
• cannabis
• GHB (gammahydroxybutrate)
• opioids
• some solvents and inhalants.

Some immediate effects include:

• difficulty concentrating
• drowsiness
• unconsciousness
• reduced coordination
• nausea and vomiting
• feeling relaxed
• decreased inhibition
• slow reaction time.

Stimulants

Stimulant drugs speed up the messages going between the brain and the body. They can make a person feel more awake, alert, confident or energetic. Large quantities of stimulants can "over-stimulate" a person, causing anxiety, panic, seizures, headaches, stomach cramps, aggression and paranoia. Prolonged or sustained use of strong stimulants can also cause these effects.

Stimulant drugs include:

• caffeine
• ephedrine (used in medicines for bronchitis, hay fever and asthma)
• nicotine
• amphetamines
• cocaine
• ecstasy (MDMA, methylenedioxymethamphetamine).

Some immediate effects of stimulants include:

• dilated pupils
• increased heart rate and blood pressure
• increased body temperature
• increased energy
• feeling more awake and alert
• headaches
• reduced appetite
• stomach cramps
• increased confidence
• talkativeness
• sleep disturbances
• agitation, anxiety and panic
• aggression and paranoia.

Hallucinogens

Hallucinogens distort a person's perception of reality. People who have taken them may see or hear things that aren't really there, or what they see may be distorted in some way. The effects of hallucinogens vary greatly.

Hallucinogenic drugs include:

• datura
• ketamine
• LSD (lysergic acid diethylamide)
• magic mushrooms (psilocybin)
• mescaline (peyote cactus)
• PCP (phencyclidine).

Cannabis is a depressant as well as a hallucinogen. Ecstasy can also have hallucinogenic qualities.

Some immediate effects of hallucinogenic drugs include:

• dilation of pupils
• loss of appetite
• stomach cramps and nausea
• increased activity, talking or laughing
• feelings of euphoria and wellbeing
• hallucinations and distorted sensory processing, including visual, auditory, bodily, time and space perception
• panic and paranoia
• loss of contact with reality, irrational or bizarre behaviour.

General effects

The effects of any drug vary from person to person. Drug effects depend on many factors, including:

• the person's size, weight, metabolism and general health and wellbeing
• how much of the drug is used
• how the drug is taken (injected, inhaled, snorted, smoked, or taken orally or anally)
• whether the person is used to taking it (the first time a person uses a drug, he or she will have a very low tolerance—in general, the more often the drug is used, the less intense the effects will be)
• whether other drugs are also taken (combining drugs can have unpredictable, unpleasant and dangerous effects)
• the person's mood and the environment in which the drug is used (people are more likely to enjoy the experience in a comfortable social atmosphere than in a threatening environment).