The Poison Lab

Mini Episode: Fundamentals: Testings Tests, Addictions vs Dependence, How Do We Alter Drug Absorption, What Do Drugs Do?

Episode Summary

In this mini-episode Ryan and Toxo use superheros, corn, and thermostats to break down some important concepts in toxicology including sensitivity, specificity, bioavailablity, dose reponse relationships, addiction and dependence

Episode Notes

Concepts in this episode

1. testing our tests
   • Sensitivity: Rate of Positive test in those who have the disease
   • Specificity: Rate of negative test in those without the disease
   • Positive predictive value: True positive/ True Positive + False Positive
   • Negative predictive value: True negative/True negative + False negative

• (PK) Bioavailablity = Amount of drug available to be used by the body
  • Oral Bioavailablity= Dose- Fraction excreted unchanged- Fraction metabolized in gut- Fraction metabolized by liver 
• How drugs interact with the body (PD)
  • Agonist- stimulates receptor
  • Partial agonist- Activation of receptor with ceiling effect, never achieves maximal activation
  • Antagonist- Prevents receptor activation
  • Inverse agonist- induces an opposite effect as an agonist after binding receptor
• Addiction vs dependance
  • Addiction- Relationship between user and substance
    • A few definitions but frequently involving consequences in life from use and loss of control over use of substance
  • Dependence- Physiologic changes in body due to chronic use
    • Down regulation of stimulated receptors
    • Physiologic basis for tolerance and withdrawal