• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/46

Click to flip

46 Cards in this Set

  • Front
  • Back
Pharmacokinetics
study of drug movement throughout the body

absorption, distribution, metabolism, excretion
absorption
movement of a drug from its site of administration into the blood
distribution
movement from blood to interstitial space of tissues then into cells
metabolism
enzymatically mediated alteration of drug structure
excretion
movement of drugs and their moetabolism out of the body
Benefits of pharmacokinetics to nurses
1. less likely to commit med errors
2. challange physicians
3. increase job satisfaction
Rate of absorption determines....
physical and chemical properties of drug and the physiologic and anatomic factors at site of absorption
The amount of absorption determines
how intense the effect will be
5 factors to drug absorption
1. rate of dissolution
2. surface area
3. blood flow
4. lipid solubility
5. pH partioning
How does rate of dissolution affect absorption
the drug has to be dissolved before it can be absorbed
How does the surface area affect absorption
the larger the surface area, the faster the drug can absorb
How does blood flow affect absorption
drugs are absorbed more rapidly where blood flow is highest
How does lipid solubility affect absorption
high lipid-soluble drugs are absorbed more rapidly and can readily cross the membranes that seperate them from the blood
Enteral
through the GI tract
Parenteral
Anything you do not swallow
outside the GI tract
There are no barriers to absorption when
the drug is administered IV right into the blood
4 advantages of IV administration
1. rapid onset-emergencies
2. control
3. use of large fluid volumes
4. use of irritant drugs- not as irritant through IV
5 disadvantages of IV administration
1. high cost, difficulty, inconvenience
2. irreversibility
3. fluid overload
4. infection
5. embolism
Barrier to IM administration
capillary walls- not significant barrier
2 factors affecting rate of absorption during IM route
1. water solubility
2. blood flow
2 advantages of IM route
1. rate of absorption
2. depot preperations- drug is absorbed slowly over long periods of time
2 disadvantages of IM route
1. discomfort
2. inconvenience
Major barrier to absorption when drugs are given orally
epithelial cells in GI tract
capillary walls
6 factors that can affect rate and extent of absorption administered orally
1. solubility and stability
2. gastric and intestinal pH
3. gastric emptying time
4. food in gut
5. coadministration of drugs
6. special coating on drugs
When a drug is swallowed and absorbed in the GI tract, what organ must it pass through
liver
2 advantages of oral route
1. convenient
2. inexpensive
4 disadvantages of oral route
1. variability- difficult to control concentration
2. inactivation
3. patient requirements- requires concious and cooperative
4.local irritation
Chemical equilalence
if they contain the same amount of a drug
Bioavailability
if the drug they contain is absorbed at the same rate and to the same extent
2 purposes of enteric coated tablets
1. protect drug from acid and pepsin in stomach
2. protect stomach from drugs which could cause gastric upset
How do sustained release capsules work
filled with spheres that contain drug, spheres have coatings that dissolve at variable rates
6 aditional routes of administration
1. topically
2. transdermal
3. rectal supositories
4. vaginal supositories
5. inhaled
6. direct injection
Topical
local therapy of skin, eyes, ears, nose, mouth and vagina
Transdermal
through skin
3 major factors affeting distribution
1. blood flow
2. ability of drug to exit vascular system
3. ability of drug to enter cells
Where does most drug metabolism take place
liver
Most important consequence of drug metabolism
promotion of renal drug excretion
Prodrug
compound that is pharmacologically inactive as administered and then undergoes conversion to active within the body
Drug excretion
removal of drugs from body
6 ways drugs can exit the body
1. urine
2. bile
3. sweat
4. saliva
5. breast milk
6. expired air
3 processes that result in urinary excretion of drugs
1. glomerular filtration
2. passive tubular reabsorption
3. active tubular secretion
Minimum effective concentration
the plasma drug level lowest at which therapeutic effects will not occur
Toxic concentration
when plsma drug levels are too high
Therapeutic Range
enough drug present to produce therapeutic responses but not too much to be toxic
Loading Dose
large initial dose
shorten times to plateau
Maintenance Dose
smaller doses to maintain a therapeutic level