Pharmacokinetics and Pharmacodynamics (complete) Flashcards
What is pharmacology?
the science of looking at composition, effects, and uses of drugs
Drug classifications: classified by effects on…
- particular body system
- therapeutic use
- chemical characteristics
- can fall into multiple categories
What is a prototype?
- usually the first medication in a class
- standard in which other drugs are compared to in the class: better or the same?
– morphine
– fluoxetine (Prozac)
– captopril
What is the generic name?
- official name of the medication
- never changes
- must meet same FDA standards
- helps indicate what class a drug falls into (“pril”, “olol’, “statin”
designated by lowercase letter
What is a trade or brand name?
- decided and parented by the manufacturer
- can be several different names
- have FDA approven
Example:
- Prinivil and Zestril (lisinopril)
- Advil (ibuprofen)
What is pharmacodynamics?
Interaction between the living system (person) and the foreign chemicals
How a drug affects the body:
- replaces or acts as a substitute for missing chemicals (ex: insulin)
- increase or stimulate certain cellular activities (ex. beta agonists)
- depress or slow down certain activities (ex. beta blockers)
- interfere with the functioning of foreign cells like microorganisms or neoplasms (ex. antibiotics or chemo)
What are receptor sites?
- receptor site reacts with specific chemicals to cause an effect on the cell
- drugs act on specific areas on cell membrane proteins that each perform a specific function
– lock and key - effect can be to increase or decrease cellular activity
What are agonists?
Occupy and activate receptors
Types:
- full agonist
- partial agonist
What is a full agonist?
Does not need all the sites to produce the desired effect
- can be as little as 10%
Example: morphine, albuterol
What is a partial agonist?
Fall in between - turn on some action, but not completely
- only stimulate some of the receptors (intrinsic activity)
- can act as both agonist and antagonist
– beta blockers with ISA do not lower HR as low as pure antagonists
What are antagonists?
- occupy receptors, but do not stimulate them
- keep the agonist from occupying the same spot and producing a response
Examples
- beta blocker
- charcoal
- naloxone
What is an agonist/antagonist?
Only stimulate some of the receptors and others are blocked
Example: suboxone
What is acute therapy?
usually the patient is very ill and needs immediate therapy
What is empiric therapy?
Medications given because of practical experience and known data
Example: antibiotics for a UTI because most UTI are either E. coli or staph saprophyticus
What is maintenance therapy?
maintains steady dose for chronic conditions that do not resolve
like hypertension
What is supportive therapy
Does not cure but maintains other function until the patient improves
What is palliative therapy
Used for end stage or terminal diseases to make person comfortable
- can be pain medication but also can be meds like chemotherapy
What is critical concentration
The amount of a drug that is needed to cause a therapeutic effect
What is loading dose?
- some medications take a long time to reach a critical concentration
- if the drug effect is needed quickly, a loading dose is given to reach the critical concentration
- it is a higher dose than usually used for treatment
What is the onset of a drug
time it takes to reach a minimum effective concentration
What is the peak of a drug
Occurs when drug reaches its highest blood or plasma concentration
What is the duration of a drug
the length of time the drug has a pharmacologic effect
What is therapeutic drug monitoring
Defined as the use of assay procedures (labs) to determine drug concentration in the blood
- assesses toxic levels
Therapeutic index: margin of safety of drug
- low: narrow margin of safety
- high: less danger
Variation can occur based on pharmacokinetics, disease states, and possible drug interactions
What is the therapeutic range?
Drug concentration from minimum effective concentration to the minimum toxic concentration
refers to the range of blood concentrations representing the lower and upper boundaries of “desirable” blood concentrations of a drug
- lower limit is established so that enough drug is administered to attain therapeutic effect
- upper limit established to avoid or minimize toxicity
should serve as a guide
- not all patients respond the same
- want to treat the patient, not the lab value
What is the trough drug level
- rate of elimination
- typically drawn right before the dose is administered
- lowest point of concentration
What is peak drug level
- rate of absorption
- usually several hours after taking; depends on the med
- about an hour to peak according to professor but is determined by drug