drugs

• some drugs just relieve symptoms - others cure the problem
• painkillers - are drugs that relieve that pain. however, they don't actually tackle the cause of the disease or kill pathogens, they just help to reduce the symptoms
• antibiotics - they work differently, they actually kill (or prevent the growth of) the bacteria causing the problem, without killing your own body cells.
• antibiotics don't destroy viruses
• viruses reproduce using your own body cells, which makes it very difficult to develop drugs that just destroy the virus without killing the body's cells
• the use of antibiotics has greatly reduced the number of deaths from communicable diseases
• many drugs originally came from plants
• plants produce a variety of chemicals to defend themselves against pests and pathogens
• some chemicals from plants can be used as drugs to treat human diseases or relieve symptoms
• a lot of current medicines were discovered by studying plants used in traditional cures, for example:

  • aspirin is used as a painkiller and to lower fever - it was developed from a chemical found in willow
  • digitalis is used to treat heart conditions - it was developed from a chemical found in foxgloves
• some drugs were extracted from microoragnisms, for example:

  • alexander fleming discovered that mould (called penecillin notatum) produces a substance that kills bacteria