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Science

Drugs

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Drugs are chemicals that cause changes in the body. They can be divided into legal and illegal drugs. Drugs can also be medical (drugs taken to cure illness) or recreational (drugs taken because they have pleasing effects). Some drugs can be addictive – more and more is needed to achieve the same effect. Drugs can be separated into categories – solvents, painkillers, depressants and stimulants.

Types of drug

Drugs can affect nerves impulses, reaction times and behaviour.

Stimulants

cup of frothy coffee

Coffee is a stimulant

Stimulants include caffeine - found in fizzy drinks, tea and coffee, cannabis and amphetamines such as speed. They increase the transmission of signals from one nerve cell to the next, which then increases alertness, heart rate and breathing rate. However, in the long term, stimulants can produce 'highs' and then extreme 'lows' or even depression. They can be addictive because the body needs a constant 'top-up' to maintain the effect.

Sedatives

Sedatives or depressants include alcohol and barbiturates (such as the prescribed drug amytal and the illegal GHB). Sedatives are also drugs prescribed by a doctor to help people sleep or to relieve the symptoms of stress. They slow down the nervous system and reactions.

Painkillers

white pills

Painkillers like paracetamol and aspirin are available 'over-the-counter' at pharmacies.

Painkillers or analgesics include paracetamol, aspirin, heroin and morphine. They block nerve impulses from the painful part of the body, or block nerve impulses travelling to the part of the brain responsible for perceiving pain.

Paracetamol is an effective painkiller but an overdose is very dangerous. An overdose damages the liver and can cause death.

Hallucinogens

Hallucinogens change the way our brains work, distorting our senses. This changes our response to what we see, feel and hear. LSD is an example of a hallucinogen.

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