Medical

• Vaccination


  Introducing small quantities of dead or inactive forms of pathogen into the body
• Vaccines


  • Cannot lead to the disease in the patient
  • Stimulate white blood cells to produce antibodies against the dead or inactive pathogen
  • White blood cells can divide by mitosis to produce lots of copies of themselves
  • Copies of white blood cells can stay in the blood for decades
  • Can produce the correct antibodies quickly if the same pathogen enters the body later
• Vaccination


  Directly protects us from infection by pathogens
• Antibody level


  Rises very quickly to a very high level when the real pathogen invades the body, due to the vaccination
• It is really important that a very large number of people are vaccinated against pathogens
• Herd immunity


  When enough people are vaccinated, it also protects unvaccinated people because the pathogen cannot spread
• You'll find plenty of questions on vaccination in my revision workbook
• Antibiotics


  Drugs that kill infected bacteria inside the human body without harming body cells
• Antibiotics mean that most bacterial diseases are treatable
• Antibiotic resistance is a problem where certain antibiotics are no longer effective against certain bacteria
• Antibiotic resistance


  Bacteria have evolved to become resistant to certain antibiotics due to overuse
• Antibiotic resistance is a serious problem as it may make bacterial diseases very difficult to treat in the future
• Doctors are careful when prescribing antibiotics, using specific antibiotics to treat specific bacteria
• Antibiotics cannot kill viruses, so doctors will not prescribe them for conditions caused by viruses
• Painkillers


  Drugs that treat the symptoms of a disease by relieving pain, but do not kill pathogens or treat the disease itself
• Viruses live and reproduce inside human cells, making it difficult to develop drugs that kill viruses without also damaging body tissues
• New medicines


  Developed all the time, have to be extensively tested
• Sources of new medicines

  • Extracted from plants
  • Extracted from microorganisms
  • Synthesized by chemists
• Drug testing process


  1. Preclinical testing on cells, tissues, or live animals

  2. Clinical testing on healthy volunteers to check safety

  3. Clinical testing to find optimal dose
• Placebo


  Tablet or injection with no active drug
• Double-blind trial


  Test group receives active drug, control group receives dummy drug, neither patients nor doctors know who is receiving what
• Double-blind trials are to stop bias in case doctors pay closer attention to people receiving the active drug