Use and Abuse of Drugs

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Drugs are substances that alter the way the body works in some way.  Drugs can be beneficial but may harm the body.  Many drugs can only be used if they have been prescribed by a Doctor.  They may be used to treat, cure or prevent diseases.  Your Doctor may prescribe drugs for a short period of time e.g. antibiotics given to treat an infection or they may be used to treat long-term (chronic) illnesses such as heart disease or cancer.   Many drugs in use today have been developed from natural substances and these were often used originally by indigenous peoples.  Indigenous people are the original inhabitants of an area such as Indians living in the Amazon rain forest or Aboriginals living in Australia.


The pictures show some common drugs.  Coffee, Cigarettes and Wine contain caffeine, nicotine and alcohol which all affect the body.  Cannabis is an illegal drug and prozac can only be used when prescribed by a doctor.  (Photos take from Wikipedia)

Legal Drugs

Cigarettes and alcohol are legal drugs that can be used once you have reached the age of 18.  It is illegal for shopkeepers to sell these drugs to young people under the age of 18.  Alcohol affects the nervous system and slows down reactions and helps people relax.  However, too much alcohol may lead to a lack of self-control, unconsciousness or even coma.  Excessive drinking can damage the liver and brain.

Tobacco smoke contains nicotine which is addictive.  Stopping smoking may cause severe withdrawl symptoms which may be helped by nicotine replacement therapy (NRT).  In NRT the patient is often given controlled doses of nicotine either by sticking a patch on their arm or through the use of chewing gum which contains the drug.  Nicotine is a stimulant (makes you more alert).  Tobacco smoke contains a large number of different chemicals, many of which are carcinogens which may cause cancer.  Tobacco smoke also contains carbon monoxide which reduces the amount of oxygen that can be carried in the blood.  If a pregnant woman smokes, she may deprive the fetus of oxygen and this may lead to a low birth mass in the baby. 


The images show the appearance of a normal liver and the liver from a person with cirrhosis.  Smoking can lead to diseases of the lung such as lung cancer and emphysema.  Amy Winehouse is a well known celebrity who is said to suffer from emphysema.  A normal lung would not have the black patches shown above which are damaged regions of the lung.


Illegal Drugs

Many drugs are illegal wherever they are used, whereas other drugs may be used legally under certain circumstances.  Drugs such as tobacco and alcohol are legal drugs which are used recreationally - i.e. for the enjoyment or pleasure of the user.  Many recreational drugs are illegal and many of these are harmful.

Cannabis is an illegal drug.  The smoke contains chemicals which may cause mental illness in some people and cannabis has been associated with anxiety and depression.  Studies carried out by some scientists appear to indicate that cannabis use may lead to the use of harder drugs such as coccaine or heroin.  However, other scientists believe there is no good evidence  for this.  You need to be able to evaluate these claims critically based upon data that may be presented to you.  If you would like to find out more about these conflicting ideas, click here.

The overall (negative) impacts of legal drugs on health is much greater than the impact of illegal drugs because far more people use them.  For example, overuse of alcohol may lead to people missing days off work due to hangovers or people needing treatment for diseases such as cirrhosis of the liver.  Similarly, smokers are more likely to suffer from ill health than non-smokers.