Drugs

• Some relieve the problem, some cure the problem

  • painkillers (aspirin) are drugs that relieve pain but they don't actually tackle the cause of the disease or kill the pathogen
  • some reduce the symptoms without tackling the underlying cause
  • antibiotics (penicillin) works differently they kill the bacteria causing the problem without killing body cells - different antibiotics kill different bacteria
  • but they don't destroy viruses (flu)
  • the use of antibiotics has greatly reduced the number of deaths from communicable diseases caused by bacteria
• bacteria can become resistant to antibiotics

  • bacteria mutates - this causes them to be resistant to an antibiotic
  • if you have an infection - some might be resistant to antibiotics
  • this means that when you treat the infection only the non-resistant strains will be killed
  • the resistant bacteria will survive and reproduce - population will increase
  • the resistant strain can cause serious infection that can't be treated
  • to slow down the rate of development you will have to not over use the antibiotics and finish the whole course
• Many drugs came from plants

  • plants produce a variety of chemicals to defend themselves against pest/ pathogens
  • the chemicals can be used to treat human disease or relieve symptoms
• Aspirin - is used as a painkiller and to lower fever - found in willow

  Digitalis - used to treat heart conditions - found in foxgloves
• some were extracted from microorganisms

  • Alexander Fleming was clearing out some Petri dishes containing bacteria - he noticed that in 1 dish also had mould but the area around the mould was free of bacteria
  • he found that the mould was producing a substance which was killing the bacteria