Pharmacology Quiz 2 Flashcards
Pharmakon-
drug or poison
kinesis
motion/movement
What term answers these questions?
-How does the drug get into the body and where does it go?
-What does the body do with these drugs?
-How does the body get rid of the drugs?
Pharmacokinetics
What system uses absorption?
GI Tract and other sites of administration
What system is used during distribution?
circulatory
What organs are used during metabolism?
liver, kidney, and sites of action
What liquids are excreted out of the body during excretion phase?
bile and urine
Absorption definition
movement of a drug from site of administration into the blood
Rate definition
how soon effects take place
The amount of medication is also known as the
intensity of effects
What factors affect the process of absorption?
rate of dissolution (dissolves)
the surface area where absorbed
blood flow
lipid solubility
pH partitioning
Route of administration
Enteral Route of Administration
oral (PO)
Parenteral Route of Administration
Outside of GI Tract
IV, SubQ, IM
PO, per os =
by way of mouth
Advantages of Oral Routes
safer than injection sites
ideal for self-medication
easy
convenient
cheap
Disadvantages of Oral route
GI irritation
requires cooperation
inactivation
variability
Barriers affecting Oral Routes
epithelial lining in GI Tract
capillary wall
What barriers affect IV routes?
no barriers
IV dose Advantages
rapid, constant, complete, control, use of large fluid volumes, use of irritant drugs
IV dose Disadvantages
irreversible
infection
high cost
difficult
inconvenient
high risk for embolism or given too fast
What barriers are in Intramuscular (IM) and SubQ injections?
No barriers (capillary wall through the fenestration)
IM and SubQ doses are absorbed rapidly with what variables? (Select all that apply).
Water Solubility
Poor Water
Dehydrated fruits
Rapid blood flow
Water Solubility
Blood Flow
What are the advantages of IM and SubQ routes of injections?
allows for poorly soluble drugs to enter the body
depot preparations
What is a depot preparation drug?
a drug that is absorbed slowly over an extended time (days, weeks, or months)
What is an example of a depot preparation drug?
Penicillin, some antipsychotic drugs, and hormones
What are some disadvantages of IM and SubQ drug routes?
discomfort, inconvenience, bleed risk
If done improperly, cause muscle and nerve injuries
What are some disadvantages of IM and SubQ drug routes?
discomfort, inconvenience, bleeding risk
If done improperly, cause muscle and nerve injuries
When are parental routes of admission preferred?
emergencies
tight control of drugs
GI incompatibility (drug destroyed or cause injury)
treatment can’t cross membranes
better treated with long-acting depot preparation
patient uncooperative orally
Distribution definition
movement of drugs through the body
The effectiveness of distribution is based on what?
blood flow to tissues
ability to enter cells
exit vascular system
Metabolism definition
enzymatic/chemical alteration of drug structure to a more water-soluble form that can be excreted
What affects the metabolism of a drug?
Age
first pass effect
nutritional status
competition between drugs
What is the first pass effect?
rapid hepatic inactivation of certain oral drugs
What organ has the most drug metabolism taking place?
Liver
What drug is known to have the 1st pass effect and needs to be delivered sublingually?
Nitroglycerin
If a drug has an extremely high to be metabolized by the liver, then it can be completely inactivated. What does this demonstrate?
the first-pass effect
Excretion definition
removal of drugs from the body
What are some examples of excretions?
bile, urine, feces, sweat, saliva, breast milk, expired air
What organ does most of the excretions?
Kidneys
Plasma drug levels show what?
correlation between response to drug and level of plasma
What 2 levels are important for monitoring responses of drugs?
Minimum effective concentration and (maximum) toxic concentration
The therapeutic range is used to determine the?
dose of a drug given safely
What does a drug’s half-life (dosing interval) represent?
percentage of drug in the body is less than 50 percent
What is the half-life of morphine?
3 hours
What does repeated dosing lead to?
drug accumulation
When the amount of drug eliminated between doses equals the dose administered, what does that mean?
average drug levels will remain constant and a plateau will have been reached
Peak in Med Plateau means
max amount in the body
Trough in Med Plateau means
lowest level of drug in the body
Loading in Med Plateau means
higher dose to level up the drug in the body
Pharmacodynamics
power of drug
Dose-response relationship means
between the size of the administration dose and intensity of response produced
ED50 means
average effective dose (standard when starting a new patient on a medication)
LD50
lethal dose
Therapeutic Index formula
LD50/ED50 (bigger is better and wider is safer)
Potentiate means ________ the effects.
intensifies
Inhibit means ________ the effects.
reduce
New response is only seen when?
drugs are combined
Drug to Food Interactions do what?
Increase absorption
drug metabolizes increase or decrease
toxicity
action by reducing or intensifying
timing during meal times
Grapefruit juice has what type of on drugs?
drug metabolizes longer
