drugs affect our body chemistry. medical drugs are developed and tested to relieve illness or disease. drugs may also be used recreationally as people like the effect on the body, e.g. alcohol and tabacco. some drugs are addictive. some athletes take drugs to improve performance. people cannot make sensible decisions about drugs unless they know their full effects.

  • Created by: Harri
  • Created on: 06-06-11 16:55


drugs are substances that change the chemical processes in your body. people who have inhabited a region since ancient time (indigenous people) have prepared drugs from natural sources for many years.

solvents, alcohol, tabacco and many other drugs may harm your body. hard drugs such as cocaine and heroine are very addictive and can cause serious health problems.

withdrawal symptoms from drugs can include; cravings, holusinations, depresion, insomnea, cold sweats, nausia, shivering.

drugs can be illegal and legal for example, alcohol is legal only to people abouve an age limit or some medical drugs are only legal to those with perscriptions.

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Developing new Drugs

researchers target a disease and develop ideas for treatment. the search for possivle drugs includes the computer design of molecules and screening hundreds of thousands of chemicals. possible drugs are made (synthesised) in the lab. in vitro (in test tubes) screening- the potential medcines are tested on cell cultures, tissue cultures and iscolated whole organs in the lap. many chemicals fail at this stage because they dont work or are toxic. the small number of chemicals which make it this far are tested on animals. this finds out more about how they work in a whole living organism. it tells us what dose is needed and sees if they cause any side effects.either (animal testing continues to look for longer term side effects) or: (chemic testing on humans begins with phase 1 on a small number of healthy volenteers, this looks at the safety of medecine in people. Human phase 2, trials run with a small number of patients suffering from the target disease. this is where scientists can really begin to see if the drug will be safe and effective. human phase 3, trials continue with larger numbers of patients.) when medicine has passed all the tests set down in law, it will ve granted a licence. now your doctor can use the new medicine to treat you ilness. once the medicine is in use, phase 5 trials continue. the medicine will be monitered for as long as the patients use it. this makes sure it works and is safe as long as possible

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the placebo effect

the placebo effect is where a control group in a drug test are given a fake drug, e.g. an injection of sugar and water, but they believe it is a drug so their illlness goes away. when the control group know that the drug is fake then they might not get the placebo effect.

to test proberly,  a blind trial should take place, where the test group and control group dont know which is which. a double blind trial is where niether the people taking the results nor the the people being tested know who has taken the real drug.

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when yeast anearobicly respirates, it ferments and makes alcohol. alcohol is a depressant because it slows down your nervous system.

in most people the liver and kidneys remove one unit of alcohol from the body every hour if they drink a reasonable amount of water. hangovers are caused by the alcohol making the kidneys release more water than you drink, making you dehydrated. coffee makes you worse by making you urinate even more.

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it was developed as a sleeping pill, found to be effective in releaving moring sickness during pregrancy, however it had not been tested for this purpose. so the effects on the unborn foetus was unknown. many babies born to the mothers who had taken the drug had severe limb abnormalities. it was then banned, but now is being used to treat leprosy and cancer.

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Performane Enhancing Drugs

steroids are the most commonly used performance inhancing drugs used by athletes involved in power sports, for example weight lifting. the percieved benefitsand side effects  include :

  • increased muscle bulk
  • increased muscle strength
  • faster muscle recovery
  • reduced muscle breakdown following intense exercise which helps muscle recovery and development
  • decreased sperm production
  • increased aggression, irratability and mood swings
  • liver disorders
  • acne
  • baldness
  • high blood preassure
  • raised cholesterol
  • gynecomastia (in men) or hirsuitsm (in women)
  • menstrual irregularties
  • deepening of the voice
  • reduced immunity
  • tumors
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Canabis Class

People who take canabis when they are a teenager ar much more likely to become addicted to heroine later in life. this is a reason for giving canabis a higher legal classification

why canabis should a class A or B drug:

it causes mental illness, it can lead to addiction to more dangerous drugs later in life

why canabis should not be classed as an illegal drug

it is not as addictive as tabacco, which is a legal drug and it does not cause many social problems

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