Week 3: Efficacy and Potency Flashcards
What is efficacy of a drug?
How good the drug is at their job
What is potency of a drug?
strength, how strong the drug is
What is the relationship between drugs and receptors?
- drugs are chemicals that can only produce effects that are physiologic activities normally regulated by the body’s receptors
- they essentially mimic or stop what our bodies are doing
What are agonists? (3)
- Mimic the action of endogenous (inside body) regulatory hormones
- partial agonists
ex. Beta agonists (gas exchange drugs)
What are antagonists?
- block/prevent the action of endogenous regulatory molecules
- non-competitive vs competitive
ex. Beta blockers (perfusion drugs0
What do non-competitive antagonist drugs do? (3)
- “plug the keyhole” irreversibly
- prevent drug from attaching
- ex. KETAMINE
What do competitive antagonist drugs do? (2)
- compete with drugs at the keyhole and whichever has the highest concentration will attach
- reversible
How is naloxone a competitive antagonist drug?
It blocks opioids until plasma concentration levels drop below opioid blood level
- repeat dose
What are the four primary receptor families?
- Cell membrane-embedded enzymes
- Ligand-gated ion channels
- G Protein-Coupled receptor systems
- transcription factors
What is the therapeutic INDEX?
- measure of a drug’s safety
What does it mean if a drug has a small or narrow therapeutic index?
- unsafe or high risk for toxicity
- the smaller the number, the more dangerous
ex. Phenytoin (dilantin) has a TI of 2
Why is the therapeutic index important?
- we use this information to help predict drug interactions
- low TI are often monitored with lab tests
What are inducers?
drugs that increase metabolism of other drugs
What are inhibitors?
- drugs that decrease metabolism of other drugs
Are OTC herbal supplements okay to use? (4)
- know benefits and risks
- safety
- medication review
- patient education