9.12 Pharmacology 2 Flashcards
Easiest way to bring plasma concentrations to a specific level and maintain it there
via IV (can control it better this way)
What causes greater plasma concentrations of a medication?
a larger dose
What type of dosing results in fewer peaks and valleys?
- smaller
- more frequent
Most serious problem with drug interactions
biotransformation -
delaying metabolism may allow drug to exert effect for prolonged period, resulting in toxic effect
Aspirin (ASA) and methotrexate are both used to treat
rheumatoid arthritis
How do ASA and methotrexate act?
- ASA displaces methotrexate on binding site of plasma proteins
- causes unbound methotrexate to circulate in the blood » increases toxicity
Primary tx of RA
methotrexate
How can drugs interact?
- can alter effects and metabolism
- can improve with greater cumulative effect than a single drug
- can cause toxicity
must monitor pt’s meds
What factors cause variations in drug response and metabolism?
- genetics
- disease
- drug interactions
- age
- sex
- other
How do genetics impact drug response and metabolism?
variations in genes that control protein synthesis
How does disease impact drug response and metabolism?
structural or functional damage to organs and tissues
How do drug interactions impact drug response and metabolism?
- additive effects
- cancel each other out
- toxicity
How does age impact drug response and metabolism? (elderly)
- elderly don’t metabolize drugs as quickly
- age-related changes in organs affect pharmacokinetics and pharmacodynamics
How does age impact drug response and metabolism? (pediatrics)
may have problems due to
- immature liver and kidney function
- differences in membrane function
- regional blood flow
- regional body comp
How does sex impact drug response and metabolism?
- men and women absorb, distribute, and metabolize drugs differently
- hormonal differences
- GI function and enzyme activity may differ
