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What are drugs?

  • Drugs are substances that change chemical reactions in the body.
  • Medical drugs relieve disease and illness, and are extensively tested before being used.
  • Recreational drugs such as alcohol and tobacco are taken by people because they like the effects they have on their bodies, but they may be addictive.
  • Cannabis and heroin are illegal recreational drugs that are very addictive.
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Double blind trials

  • Apart of testing drugs is to be certain that the medication is having a real affect on the body, rather than it making the patient feel better, simply because they believe they are. This is called a placebo effect. 
  • Double blind trials aim to minimise the placebo effect by giving some patients in the trial a placebo, and others the real drug. A placebo is designed to appear exactly the same as the drug itself, but it does not actually contain any of the drug. 

This helps to test whether the drug really works, as no one involved is told if the drugs they are taking are real or not, until the trial is over.

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  • Thalidomide is a medical drug that caused unexpected and serious damage to unborn babies in the 1950s and 1960s.
  • It was originally used as a sleeping pill at first, however was discovered that it treated morning sickness.
  • However, as it was never tested on pregnant women, it caused severe birth defects, ecspecially if it was taken in the first four weeks of pregnancy.
  • The drug led to the arms or legs of the babies being very short or incompletely formed. More than 10,000 babies were affected around the world.
  • As a result of this disaster, thalidomide was banned. Drug testing was also made more strict than before.
  • Thalidomide is now used as a treatment for leprosy and bone cancer. Its use is heavily regulated, however, to prevent a repeat of the problems it caused in the last century
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Developing new drugs

New drugs are tested on cells first to see if they are toxic or if they are effective at all

They are then tested on animals, which is legal, to test for side affects and harm.

The drug is then given to healthy people, to test for side affects and any harm that was not picked up in the previous stages. If the drug is deemed safe, the very low dose given, is increased until an optimum is found. This is when patients are used to discover the best dosage suited for disease. This stage is called the clincal trials. 

Clinical trials are not without risk. Sometimes severe and unexpected side effects occur. Most substances do not pass all of the tests and trials, so drug development is expensive and takes a long time.

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Legal recreational drugs


  • Small amounts are used for relaxation and socialisation
  • Large amounts can lead to lack of self control and excessive amounts can lead to illness and comas.
  • Alcohol is addictive
  • Long-term effects of alcohol include damage to the liver and brain, and it is often the cause of weight gain


  • Highly addictive
  • It reaches the brain within 20 seconds
  • Can lead to
    • heart disease and strokes
    • miscarriage, premature birth and low birth weight
    • lung cancer, mouth cancer and throat cancer.
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Illegal and performance enhancing drugs

Illegal drugs include prescribed drugs that are dangerously modified and drugs banned by law

Drugs affect us by:

  • Indirectly causing health problems (not having enough money for food, or placing users in dangerous situations)
  • Addiction can lead to crime or danger to pay for drugs.
  • Unclean needles can lead to HIV and hepatitus

Performance enhancing drugs artificially help boost an athletes performance by

  • boosting heart rate and other bodily functions- Stimulants
  • stimulate the growth in muscles- anabolic steroids

The use of performance enhancing drugs is widely seen as unfair. They may also damage the athlete’s body.

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