PD Flashcards
Pharmacodynamics
What the drug does to the body
Ion Channels
Ligand vs. Voltage-gated
Seconds to respond
Nicotinic & GABA
GPCR
Receptor family
Activates 2nd messenger
Muscarinic/cholinergic, adrenergic, dopaminergic, opioid
Transmembrane Receptor
Transmembrane embedded enzyme-linked receptors
Growth & development
Insulin
Intracellular Receptor
Proteins found inside the nucleus
Hydrophobic ligands
Modify gene transcription
Steroid hormones & Vitamin D
Ligand
Chemical substance that binds to receptors
Endogenous
Naturally occurring
Exogenous
Drugs
Lock & Key Theory
Stereochemistry
Agonist
Activates receptors
Causes intrinsic activity
Antagonist
Receptor affinity
No intrinsic activity
Competitive vs. non-competitive
Allosteric
Makes receptors more available to endogenous substances
Potency
Affinity
How much drug to get an effect?
Efficacy
Effect
Does drug produce desired effect?
Variability
Nothing exactly the same
Not one-size-fits-all
Individual
Genetic differences, age, gender, comorbidities, dietary & supplements, drug-drug interactions
Slope
Safety margin
ED50
Effective dose - desirable effects in 50% population
TD50
Toxic dose in 50% population
Adverse side effects
Bradycardia, hypotension, N/V
LD50
Lethal dose in 50% population
Therapeutic Window
TD50/ED50
Dose to treat disease effectively while staying w/in safety margin
Desirable effects w/ minimal adverse SE
How much drug to achieve 100% efficacy
Effect w/out toxicity
Above range = serious harm
Below range = subtherapeutic dosing (inefficacious)
Therapeutic Index
LD50/ED50
How much drug required to cause adverse effects
Partial agonist
Activates receptors
Causes intrinsic activity
Not 100% efficacy
Inverse agonist
Causes opposite effect
Down-Regulation
Desensitization resulting from continued stimulation (agonist)
Quantitative - receptor decrease in number
Qualitative - each receptor becomes less responsive
