Shared Flashcard Set

Details

Pharm lecture 1 & 2
pharmacokenetics and dynamics
79
Pharmacology
Graduate
06/06/2010

Additional Pharmacology Flashcards

 


 

Cards

Term
What is a drug?
Definition
ANY biologically active compound that affects processes of living tissues
Term
What is pharmacology?
Definition
Biomedical science concerned with interactions of chemicals (drugs) with living materials
Term
What is Pharmacokinetics?
Definition

actions of the BODY on the DRUG

 

processes that determine the concentration of drugs in the body fluids and tissues over time

Term
How is pharmacokinetics broken down?
Definition

Drug absorption

distribution

biotransforamtion

excretion

Term
drug absorption
Definition

how drug absorbed from the site of administration or indirectly into plasma

(injection, skin, oral)

Term
drug distribution
Definition

distribute into the interstitial and intracellular fluids

(throughout the body to the target)

Term
drug biotransformation
Definition
metabolism of the drug by the liver, kidneys, or other tissues
Term
drug excretion
Definition
he drug and its metabolites are removed from the body in the urine, bile, or feces (sweat as well)
Term
What is pharmacodynamics?
Definition

Actions of the DRUG on the BODY

 

Biochemical mechanisms:

receptors and signal transduction

Dose-response relationships:

Potency and Efficacy

Term
Biochemical mechanisms
Definition

receptors

signal transduction

Term
Dose-response relationships
Definition

Potency (concentration-related)

Efficacy (response-related)

Term
Therapeutics
Definition

application of drugs in Prevention, Cure, Alleviation, Treatment, or Diagnosis of disease

 

business end of pham

Term
Prophylaxis
Definition
To PREVENT development of diseases
Term
Chemotherapy
Definition

Treatment of diseases caused by parasitic or invading organisms

 

only situation in which give drug to kill off and destroy an organism or cancer

Term
What types of nomenclature are used to name drugs?
Definition

Chemical name

generic- used for class

Non-proprietary

official

proprietary

brand

Term

Why aren't proprietary (brand/trade) names used in class?

 

Definition
existence of multiple names and gets confusing although may provide clues to the therapeutic action/ classification
Term
What is a tablet and capsule?
Definition

Tablet- packed 

Capsule- usually in gelatin caplet that dissolves usually faster than a thick compressed tablet

 different rates of disintegration and dissolution may cause differences in bioavalability of drugs from different tablet formulations

Term
What are different characteristics of tablets and capsules?
Definition

enteric coating- coating to protect the stomach from the drug until it passes through or to keep the drug from being dissolved until it reaches the desired location

Sustained relaese (SR) or extended release (XR):

Controlled diffusion

controlled dissolution

osmotic pressure

Term
What are solutions and suspensions?
Definition

the most common liquid pharmaceutical preparations

faster absorption than a tablet or capsule and is directly absorbed

 

Term
What are the uses for solutions and suspensions?
Definition

oral

parenteral- other than enteral ( injection, topical, drops in eye, etc)

Term
What are some preperations of solutions and suspensions?
Definition

elixirs- contain alcohol used to dissolve the drug

syrups- contain sugar to make the drug more palatable

sterile solutions

Term
What are some other preparations of drugs?
Definition

skin patches- (nicotine, hormones) drug must be available for absorption through the skin parentral

aerosols- topical (sunscreen) inhaled (asthma)

ointments, creams, lotions- more messy than skin patch

suppositories- rectal

Term
What is important to consider when testing drugs?
Definition

Risk/Benefit ratio

what are the benefits versus what are the risks

Term
How many phases are there in drug trials?
Definition

There are 4 phases

1) test on young normal males

2) test on diseased people well into disease state

3) if drug effective test again to make sure then released by FDA

4) post-marketing given out by docs and then company collects adverse rxn information to make sure drug still safe or pulled off the market

Term
How many patients are needed to indicate a significant adverse response?
Definition
10,000 
Term
What does DSHEA stand for and what is the definition?
Definition

Dietary supplement health and education act of 1994

Not intended for the diagnosis, prevention, treatment, or cure of any disease.

no regulations or studies must be done before the drug is put on the market

Term
What factors should be considered when selecting a drug?
Definition

each patient is differnt

therapy may be initiated without all the data

patient status may change

patient on multiple drugs

Term

When a drug is administered where must it be moved into for passage throughout the body?

 

Definition
systemic circulation
Term
Enteral, Parenteral, and other are what?
Definition
routes of drug administration
Term
What are examples of Enteral drug administration?
Definition

oral

sublingual- under the tongue

buccal- between cheeks and gums

rectal

Term
what are the different types of Parenteral drug administration?
Definition

intravascular- IV

intramuscular- IM

subcutaneous- SC

Term
What are other types of drug administration?
Definition

inhalation

inranasal

intrathecal- into the brain

intraventricular- into the ventricles of the brain

topical

transdermal

Term
What is the most common and variable enteral route of administration?
Definition

oral ingestion

 

Term
Why is oral the most variable?
Definition

interaction with food and gastric acid

food slows gastric emptying (less absorption)

intestinal transit- food, illness, blunt trauma

metabolism by the liver(first-pass) or gut enzymes/flora

physico-chemical properties of drug perparation

stomach v. duodenum- increased surface area and absorption in small intestine

can't use in comatose, sedated, or nauseous patients

Term
Absorption into the venous capillary network which drains into superior vena cava is an advantage of sublingual and buccal because______
Definition

bypasses GI tract and first-pass liver metabolism

 

Term
What are some drawbacks to sublingual and buccal administration?
Definition

requires low doses 

requires good solubility in water and lipid

Term
How is rectal medication prepared?
Definition

as a suppository

 

Term
When is a suppository most useful?
Definition
in children or in vomiting unconcsious patients
Term
Approximately what percentage of the drug that is absorbed by the rectum will bypass the liver?
Definition
50% which reduces the influence of first-pass hepatic metabolism
Term
What is a disadvantage of rectal administration?
Definition
often irregular, incomplete, and can cause irritation
Term
What are the main reasons for using Parenteral administration?
Definition

drugs that are poorly absorbed in he GI

for unconscious or uncooperative patients

more rapid onset

Term
What is the most common method of parenteral administration?
Definition
IV
Term
What are the advantages of IV administration?
Definition

absorption instantaneous

mainly for drugs in aqueous solutions or drugs not absorbed orally

 

Term
What are the disadvantages of IV?
Definition

cannot be recalled

chance of air emboli- gets stuck in the lungs causing pulmonary embolism

sepsis

dependent upon patient accessible veins

Term
Which type of parenteral admin is appropriate for aqueous or suspensions?
Definition

SC

suspension- not dissolved and part of the solution but remains in solid state

aqueous- dissolved in solution

 

Term
What type of parenteral admin provides slow and constant absorption and can be combined with vasoconstrictor to slow absorption?
Definition

SC

small pellet can also be implanted under the skin

Term
What type of parenteral admin is similar to subcu but provides a greater depot 
Definition
intramuscular
Term
IM absorption depends on?
Definition

blood flow to the muscle

exercise increases blood flow

Term
Why is it necessary to use Intrathecal admin?
Definition

blood brain barrier and blood CSF barrier impede entrance into the CNS

used to infections and tumor treatment

Term
Why is inhalation a good method for drug admin?
Definition

absorbed by the lungs which have large surface area for absorption which reaches the blood supply quickly and avoids first-pass metabolism

need to worry less about systemic effect and more about local effect

Term
What is the second fastest route for drug admin?
Definition
inhalation
Term
What is a disadvantage of inhalation?
Definition
site of entry for toxins and allergens
Term
What are some advantages of topical application?
Definition

local effect desired

direct application and no need for needles

 

Term
What are some routes for topical admin?
Definition

skin

eye

nasal

throat

vagina

urethra

Term
What are some disadvantages of topical application?
Definition

few drugs penetrate the skin

absorption proportional to surface area

condition of the skin affects absorption

inflammation increases cutaneous blood flow and absorption 

enhanced by suspension in oily vehicle and rubbing into skin

Term
What factors influence absorption?
Definition

phyisco-chemical properties of the barrier

  • passive, facilitated, or active diffusion

physical properties of the system

  • blood flow, surface area, contact time

physio-chemical properites of the drug

  • molecular size, lipid solubility, ionization

Term
Do smaller or larger molecules diffuse more readily
Definition

smaller <200 MW 

not applicable to facilitated diffusion, active transport, or endocytosis

Term
The____ the partition coefficient, the______ the lipid-solubility of the drug, and the greater its diffusion across the membrane
Definition
greater; higher
Term
Most drugs are small_______ ________
Definition
weak electrolytes
Term
Membranes are much more permeable to what type of ion?
Definition
non-ionized
Term
The fraction of drug that is non-ionized depends on its?
Definition
chemical nature, pKa, and pH
Term
What is the pKa?
Definition
that pH at which there is a 50/50 ratio of unionized to ionized
Term
The pKa is solely dependent upon the chemical nature of?
Definition
the drug
Term
A drug that carries an extra electron so it will always be (-) charged when not bound to an H ion is a (n)?
Definition
weak acid
Term
A drug that carries a (+) charge because it is missing an electron when bound to an H ion is a(n)?
Definition
weak base
Term
_____ are increasingly ionized with increasing pH (basic environment)
Definition
acids
Term
_______ are increasingly ionized with decreasing pH (acidic env)
Definition
bases
Term
Where would someone look if wanted to determine if there was an overdose on a weak acid?
Definition
circulatory system
Term
Where would someone look if wanted to determine if a person overdosed on a weak base?
Definition
the stomach
Term
What is the Henderson-Hasselbalch equation?
Definition
log (protonated) / (unprotonated) = pKa - pH
Term
the protonated for (HA) will ALWAYS predominate (be reabsorbed) when?
Definition
pH < pKa
Term
the unprotonated for (A-) will ALWAYS predominate (trapped) when?
Definition
pH > pKa
Term
if protonated form (BH+) will ALWAYS predominate
Definition
pH < pKa
Term
uprotonated form (B) will ALWAYS predominate
Definition
pH > pKa
Term
The fraction of administered drug that reaches systemic circulation is?
Definition
bioavailability
Term
What factors influence drug bioavailability?
Definition

solubility of drug

chemical instability

formulation

first-pass hepatic metabolism

Term
When drugs are pharmaceutical equivalents, contain the same active ingredients and are identical in dose, dosage form, and route of admin they are considered to be?
Definition

bioequivalent

only exists if the rates and extent of bioavailability of their active ingredients are not significantly different

Term
What is therapeutic equivalence?
Definition
when 2 drugs are similar if they have comparable efficacy and safety
Supporting users have an ad free experience!