Exam 1 - Drug Administration Flashcards
Pharmacokinetics
study of how drugs move through the body over time
* absorption, distribution, metabolism, excretion
* “how the body affects the drug”
Pharmacodynamics
study of how drugs affect the body
* receptor binding
* dose-response relationships
* therapeutic vs toxic effect
* potency vs efficacy
Enteral
refers to any method of delivering medications into the body through the GI tract
Examples of the enteral administration
- oral: by mouth
- sublingual: dissolving under the tongue
- rectal: drug given via rectal end of GI tract
What are the benefits of oral administration?
- convenient and economical
- relatively safe
- relatively slow and prolonged absorption
What are drawbacks of oral administration?
- irritation of GI tract
- destruction by acid or enzymes
- complex formation in GI tract
- relatively slow absorption
- unconcious or uncooperative patient
- first pass effect
First Pass Effect
initial metabolism of a drug in the liver after absorption; before it reaches systemic circulation
What are the benefits of sublingual administration?
- eliminates first pass effect
- rapid absorption
What are the drawbacks of sublingual administration?
- bad taste
- oral irritation
What are the benefits of rectal administration?
- reduces first pass effect
- easier for certain patient populations (vomiting, unconscious, neonate)
What are the drawbacks of rectal administration?
- inconvenient
- lack of compliance
Parenteral
refers to the delivery of medications directly into the body through routes other than the GI tract
What are examples of parenteral administration?
- subcutaneous: injecting into layer between skin and muscle
- intramuscular: injecting into a muscle
- intravenous: injecting into a vein
- intra-arterial
- intraspinal
What are the benefits of SubQ and intramuscular?
- useful for proteins/peptides
- can alter rate of absorption
What are the drawbacks of SubQ and intramuscular administration?
local irritation
What are benefits of intravenous administration?
- easily controlled rate of administration
- very rapid onset of action
- entire dose enters blood
What are the drawbacks of intravenous administration?
- requires sterile conditions
- not for self medication
What are the benefits of intra-arterial administration?
high dose to specific organ
What are the drawbacks of intra-arterial administration?
- danger of hemorrhage
- difficult technique
What are the benefits of intraspinal administration?
high level into CNS for spinal anesthesia and infections
What are the drawbacks of intraspinal administration?
- danger of hemorrhage
- difficult technique
What are the two types of intravenous administration? What do they mean?
- bolus: rapid injection of descrete amount (push)
- infusion: a slow continuous administration (drip)
Pulmonary
breathing a drug into the lungs
What are the benefits of pulmonary administration?
- only choice for gases and volatile liquids
- rapid, extensive absorption
