˚₊‧ʚ♡ɞ‧₊˚ 𝙿𝚑𝚊𝚛𝚖𝚊𝚌𝚘𝚕𝚘𝚐𝚢 II ˚₊‧ʚ♡ɞ‧₊˚ Flashcards
what is pharmacology?
scientific study of drugs & their effects on living organism.
what is pharmacokinetics (PK)?
How the body handles drugs; what the body does to the drug (ADME)
remember PK = Pills Kick In.
What is absorption? How can ROA affect how drugs are absorbed?
Process of drugs passing from external world into the bloodstream. ROA impact the timing of the onset of action, and also plays a role in the first-pass effect and passing through the BBB.
What are the different ROAs, and how do they absorb the drug?
Oral (ingested) absorbed through stomach/intestines; slow; easy & relatively safe; absorption via digestive tract highly variable; likely undergoes some metabolism by liver first (first-pass effect).
Mucous membranes (nose, mouth, eyes, rectum, vagina) skin: transdermal (patch, cream). | Generally faster than oral ROA; very lil metabolism prior to getting into bloodstream; sometimes damage/irritate tissue.
Inhalation (absorbed via capillaries in lungs) quick; may damage tissue; difficult to regulate dose; fastest route to brain; often has short-acting effects; not applicable for many drugs.
Injection – slow & constant rate of absorption depending on blood flow in area (subcutaneous & intramuscular are immediate & direct absorption). (intravenous 1 of the fastest routes to brain; dose can be controlled; dangerous).
What can happen with/ toxic drugs if they accumulate in an organ? What is the role of the BBB?
Some organs can be damaged from drug accumulation if it’s a toxic drug.
BBB = system of capillaries that prohibit most water-soluble substances from entering brain (acts as natural defense system)
What are metabolites?
Byproducts of the body breaking down a drug into different substance (metabolism)
What is the most common enzyme family that metabolizes drugs? What factors influence metabolism?
The liver is the most important organ for metabolism, containing the most common enzyme family that metabolizes drugs (cytochrome P-450). Factors of metabolism include genetics, size, age, sex, and other food/drugs in system.
What ways are drugs typically eliminated?
Typically done via liver breakdown & kidney filtering. Drugs often leave through kidneys as urine and GI tract as stool.
What is half-life? How do you graph and calculate the half-life of a drug?
Half-life: time it takes for half the original amount of drug in your body to be eliminated.
GRAPHING:
Imagine a graph with time on the x-axis and the amount of medicine remaining on the y-axis.
The graph starts at 100% (all the medicine) and gradually slopes downwards as the body eliminates it.
Every half-life, the amount of medicine remaining is halved. So, at the first half-life, it’s 50%, then 25% at the second, and so on.
CALCULATING:
Identifying two points on the graph where the amount of drug remaining is known.
Look at the time difference between these two points.
This time difference is close to the half-life of the drug.
What is pharmacodynamics (PD) ?
Study of how a drug exerts its effects on the body; what the drug does to the body)
PD=Pills Do What
What is a main effect vs. side effect?
Main effect: intended effect of drug.
Side effect: unintended effect of drug.
What are acute and chronic toxicity?
ACUTE:
single dose, evident in days, the dose is typically higher than chronic; symptoms MAY be reversible.
CHRONIC:
effects over long periods, may take years to become evident, typically not reversible.
What is a dose-response curve?
Helps determine effective, toxic, and lethal doses of drugs & potency (minimum dose for desired effect).
What is ED50? What is LD50? What is TD50?
ED50: effective dose for 50% of population.
LD50: lethal dose for 50% of population.
TD50: induces specific toxic effects for 50% of population.
What is the TI? How to calculate one if given the ED50 & LD50 of a drug? What does a large vs. small TI mean about the safety of a drug?
TI is like a safety rating for a drug.
Calculated with the formula: TI= LD50 ÷ ED50.
(if LD50 is 100mg & ED50 is 10mg, formula would be: TI= 100 ÷ 10 = 10).
The greater the TI, the safer the drug is considered.
