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Science

Drugs and you

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Drugs are chemicals that can alter the way the body works. There are different types of drugs, and they have different effects on the body. Tobacco and alcohol are legal recreational drugs which have potentially serious effects on the body. Illegal drugs are classified on a scale from Class A - the most dangerous - to Class C - the least dangerous.

Types of drug

Drugs alter the way the body works. Some are beneficial, while others are harmful.

The main types of drugs and their effects

type of drugeffect on the bodyexample
depressantslows down brain activityalcohol, solvents, temazepam
hallucinogenalters what we see and hearLSD
painkillerblocks nerve impulsesaspirin, paracetamol
performance enhancerimproves muscle developmentanabolic steroids
stimulantincreases brain activitynicotine, caffeine, ecstasy

Classification of drugs

Some drugs are legal, such as tobacco and alcohol. Others are illegal, or must only be prescribed by a doctor. Some prescription drugs are misused and taken for recreational use, rather than for medical reasons. They become illegal under these circumstances.

Illegal drugs are classified from Class A to Class C. Class A drugs are the most dangerous, with the most serious penalties for possession or dealing. Class C are the least dangerous, with the lightest penalties, but this does not mean they are safe to use.

Stimulants and depressants - Higher tier

Stimulants and depressants affect the synapses between neurones in the nervous system:

  • stimulants cause more neurotransmitter molecules to diffuse across the synapse
  • depressants stop the next neurone sending nerve impulses – they bind to the receptor molecules it needs to respond to the neurotransmitter molecules.

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