Developing New Medicines

• The painkiller aspirin originated from the bark of ________ trees. It is now used to reduce pain, and lower fevers. 

  willow
• The drug digitalis originated from plants known as _________. It is used to treat heart conditions such as heart failure. 

  foxgloves
• What was discovered by Alexander Fleming when some Penicillium mould contaminated one of his Petri dishes. 

  penicillin
• What does the term 'efficacy' mean?

  How well a drug produces the desired effect 
• What does the term 'toxicity' mean?

  How harmful a drug is e.g. how many side effects
• What does the term 'dosage' mean?

  How much of the drug is required to give the desired effect
• 1. Stage 1 - Test the drug on human cells and tissues.
  2. Stage 2 - Test the drug on live animals.
  3. Stage 3a - Test the drug on healthy volunteers to find the maximum dosage before side effects occur.
  4. Stage 3b - Test the drug on patients that suffer from the relevant disease, to find the optimum dosage. 
• Why is it important that new medicinal drugs undergo testing before they are used?

  To make sure they are an effective treatment

  To make sure they are safe to use

  To determine the optimum dose
• In a double blind trial, who knows who is given the trial drug, and who is given the placebo?

  Only the researcher
• Patients in clinical trials are often given a placebo.

  What is a placebo?

  A substance or treatment that contains no active drug
• Medical trials often use placebos, and are double-blind. 

  Why is it important for medical trials to be double-blind?

  It helps to avoid any bias by the patients or researchers. If patients know they received the drug, then they may be more likely to report side effects. If researchers know who has been given the real drug, then they may pay closer attention to those patents, and document their symptoms more carefully.