What separates the drug from the poison Flashcards
How can a drug be considered a “drug”?
if it can reach its target
What are some examples of drugs that are a would-be-poison?
- Imodium (made of an opioid) but doesn’t leave the gut and not addictive in the brain
- Ventolin only targets adrenoceptors in the lungs, and doesn’t cause people to go into fight of flight
- Botox injected into the skin but doesn’t travel
What attribute separates the drug from the poison?
selectivity
We cannot control where a drug goes, so we need selectivity
Where did our antibiotics come from?
natural products and screening
What’s the biggest challenge when fighting bacteria?
permeability because the drug has to pass through 2 membranes
Why is it hard to poison Tuberculosis?
Once the drug makes it to the lungs, it has to get through a barrier the consistency of candle wax
What problem do humans face with antibiotics?
we found all the antibiotics that were easy to find, over used them, and now resistance
Has an antibiotic ever been synthesized?
once, but then never done again
an impurity from the synthesis of chloroquine found its way into a screening library, now the most potent antibiotic
What is selectivity screening?
outsource broad screen against a wide range of targets - everything you don’t want to hit and aim to make the drug less potent against unwanted targets
How is a drug kept effective in the body?
preventing metabolism by blocking vulnerable point on the molecule (adding F group)
What is considered a bioavailable drug?
when it reaches the blood and there is is >50 % left
What is trying to be achieved when a drug is in the body?
a wide therapeutic window
What is a non-selective drug?
poison
