Pharmacology Exam 1 Flashcards
What is Pharmacology?
The study of drugs and their interactions with the human body. Discusses the source, physical and chemical properties, compounding, physiological actions, absorption, fate and excretion, and the therapeutic use of drugs.
List the pharmacokinetic principles.
Absorption, distribution, metabolism, and elimination.
Define absorbtion.
absorption from the site of administration permits entry of the drug either directly or indirectly into plasma.
Define distribution.
The drug reversibly leaving the blood stream and entering the interstitial and intercellular fluids.
Define metabolism.
The drug possibly being bio-transfomed by the liver or other tissues.
Define elimination.
the drug/its metabolites get eliminated from the body through the urine (kidneys), bile (liver), or feces (GI tract).
Define a drug-drug interaction.
The effect of one drug (the object drug) being changed by another drug (precipitant drug).
What are the types of drug interactions?
Drug-drug, drug-food, and drug-condition.
What are the names of the mechanisms of drug-drug ineractions?
Antagonism and potentiation/synergistic.
What occurs during an antagonism reaction?
Two drugs interact and have opposing effects, opposition in action or smaller combined effect than individual agents (2+2=1).
What occurs during a potentiation/synergistic reaction?
two drugs have an additive effect, an interaction between two drugs that generate a response that is greater than the sum of individual responses to each drug or agent (1+1=5).
What factors can effect the rate and extent of drug absorption?
The environment (if the drug is administered orally, the stomach acid PH may break down the structure or effect the chemical characteristics of the drug making it less bioavailable), the chemical characteristics of the drug (whether the drug is lipid soluble vs water soluble), and the route of administration (100% of the drug is absorbed into the plasma when administer via IV but any other way may result in partial absorption and lower bioavailability).
How do you calculate the loading dose?
Vd = amount of drug in the body(dose given)/C0
Vd = the fluid volume that is required to contain the entire drug in the body at the came concentration measured in the plasma
C0 = amount of drug in the body at time 0
What are the possible clinical effects of a CYP450 mediated drug interaction?
If the reaction is CYP450 mediated, there may be other interactions that occur. Meaning that some drugs may bind to receptors responsible for other things.
What is a GFR?
Glomerular filtration rate.
