testing medicines

• Where did medicines often come from in the past?

  They were extracted from plants
• What drug was extracted from the foxglove plant?

  Digitalis
• From which tree was aspirin extracted?

  Willow trees
• Who discovered penicillin?

  Alexander Fleming
• What is the primary source of most new drugs today?

  Synthesized by chemists in pharmaceutical companies
• What must all new drugs be tested for?

  Toxicity, effectiveness, and optimal dose
• What is the first stage of drug testing called?

  Preclinical testing
• Why is preclinical testing not carried out on humans?

  A drug could be extremely toxic
• What is preclinical testing carried out on?

  Cells, tissues, or live animals
• What happens after preclinical testing?

  The drug undergoes clinical testing in humans
• What is the purpose of the first stage of clinical testing?

  To check that the drug is safe in humans
• What is done if the drug is found to be safe in clinical testing?

  Clinical testing continues to find the optimal dose
• What is a placebo?

  A tablet or injection with no active drug
• Why might some patients get better when given a placebo?

  They believe they are being treated
• What is a double-blind test?

  Neither patients nor doctors know the treatment
• What is the purpose of a double-blind trial?

  To stop bias in treatment observation
• What are the stages of drug testing?

  1. Preclinical testing

  • Conducted on cells, tissues, or animals
  • Checks toxicity

  1. Clinical testing

  • First stage: low doses to healthy volunteers
  • Checks safety in humans
  • Continues to find optimal dose
• What are the key differences between preclinical and clinical testing?

  • Preclinical testing:
  • Not on humans
  • Focuses on toxicity
  • Clinical testing:
  • Conducted on humans
  • Focuses on safety and dosage