Drugs

• Drugs that relieve symptoms


  They don't actually tackle the cause of the disease or pathogens, they just help to reduce the symptoms
• Drugs that cure the problem


  They actually kill (or prevent the growth of) the bacteria causing the problem without harming your own body cells
• Antibiotics destroy viruses (e.g. flu or cold viruses)
• Viruses reproduce using your body cells, which makes it very difficult to develop drugs that destroy just the virus without killing the body cells
• The use of antibiotics has greatly reduced the number of deaths from communicable diseases caused by bacteria
• Bacteria can become resistant to antibiotics


  When you treat an infection, only the susceptible strains of bacteria will be killed, and the resistant strains will survive and multiply
• Developing resistance to antibiotics is a serious problem that can lead to wound infections that are difficult to treat
• To slow the development of antibiotic resistance, it's important for doctors to prescribe antibiotics only when necessary
• It's also important that you take the full course of antibiotics and don't just stop once you feel better
• Many drugs originally came from plants


  Plants produce chemicals to defend themselves against pests and pathogens, and some of these chemicals can be used as drugs to treat human diseases or relieve symptoms
• Drugs developed from plant chemicals

  • Aspirin (from willow bark)
  • Digoxin (from foxglove)
• Discovery of penicillin


  1. Nwander Fleming was clearing out some Petri dishes containing bacteria

  2. He noticed that one of the dishes of bacteria also had mould on it

  3. The mould (Penicillium notatum) was producing a substance that killed the bacteria
• Drugs are now produced on a large scale in the pharmaceutical industry, often starting with a chemical extracted from a plant
• Preclinical testing


  • Drugs are tested on human cells and tissues in the lab
  • Drugs are tested on live animals to test efficacy, toxicity, and dosage
• Clinical trials


  • Drugs are tested on healthy human volunteers to check for side effects
  • Drugs are tested on patients with the condition to see how well they work, using a placebo control group
• The results of drug testing and drug trials must be assessed by peer review before they can be published
• The placebo effect doesn't work with revision - you can't just expect to get a good mark and then magically get it
• Efficacy of a drug

  Whether the drug works and produces the desired effect
• Clinical trials of a new drug begin with healthy volunteers to test for any side effects when the body is working normally
• Drug testing results must be assessed by peer review to prevent false claims