How drugs exhibit their effects Flashcards
pharmacodynamics
study of the biochemical and physiologic effects of drugs
clinically relevant PD parameters
mechanism of action, relationship between drug concentration and effect, side effects or adverse reactions
pharmacokinetics
movement of drug molecules into, through, and out of the body. ability for living organism to absorb, distribute, metabolize and excrete a drug
absorption
movement from administration site into systemic circulation (into the blood stream); need to reach their target tissues
bioavailability
actual quantity of drug that enters into the system circulation and eventually reaches the target
distribution
movement from systemic circulation into tissues
barriers to drug distribution
drug’s chemical properties, tissue blood flow, degree of protein binding, degree of tissue binding, anatomic barriers
metabolism (biotransformation)
when the body modifies the drug so it can be excreted; mostly in liver
elimination/excretion
removal of drug/metabolite from body; kidney via urine, liver via bile and feces
how drugs exert their effects
receptor on cell wall combines with specific drug, not all drugs have the same effect
most common diseases that impact drug PK
liver disease, kidney disease, cardiovascular disease
cardiovascular disease
alters the distribution of blood flow to tissues; more blood is distributed to the brain and heart
kidney disease
decreased drug elimination, increased plasma drug concentrations, risk of toxicity, increased fluid retention, potential drug interactions
liver disease
primary site of drug metabolism; difficult to predict need for dosage adjustments
side effects
drug interacting with multiple tissue types, multiple cellular targets, alteration in patient’s physiology and/or drug pharmacokinetics
half-life
amount of time that it takes for the quantity of a drug in the body to be reduced by half
potency
strength of a drug at a particular dosage
efficacy
degree to which a drug produces its desired response in a patient
adverse drug reaction
undesirable response to a drug by a patient. may vary from mild to fatal
withdrawal time
time required after administration of the last dose of a drug and the production of meat or other animal derived products such as eggs or milk
the degree to which a drug is absorbed and reached general circulation is called bioavailability
true
the next step after a drug is administered to a patient is distribution of the drug
false
