Theraputic Drug Monitoring Flashcards
What is TDM?
Measurement of drugs and or metabolites in body fluids - usually blood- to maintain therap. benefits
Describe T.R
the dose, concentration or range of a drug within the drug produces the desired theraputic effect
Describe T.R out of range
ineffective or toxic effect
T/F most drugs require monitoring
false, most drugs dont
Important Considerations of TDM
timing of collection (important)
Accurate measurement of []
Timely reporting of results
When is TDM used
when drug has narrow T.R
marked pharmokeinetic variabilites
Critical Adverse effects
Main purpose of TDM
ID?
ensure correct dosage for the T.R
ID drug interactions if multiple drugs are taken together
Factors that affect drug concentration
Age
gender
genetics
diet
co-drugs
naturopathic
T/F: TDM can help establish dosing regimen
Can ID non-compliance or changes if needed
Based on studies pharmokin/pharmogen
TRUE
Describe Pharmokinetics
study of
provides a time?
absorb….
what place what time?
study of movement of drugs in the body
provides a time-course of drug [ ] as absorption/disturb/metabolism
Drugs at right place at right time
Describe the route of drugs intake briefly
Oral most common
IV most direct/effective
IM
Sub cutaneous
Aerosol
Rectal
Describe Bioavilability
Amount of dose that reaches site as needed
Describe drug absorption
oral efficiency
factors that influence
how does it move across the membrane?
Oral: effic. of absorb from GI tract depends on sev. factors
solubility of GI fluid
diffuse across membrane
T/F: Some drugs require active transport mechanisms like dietary consituents
true
How are most drugs absorbed? What are some things needed?
ga
Most absorbed passively through GI tract into the blood stream
Drug - hydrophobic
Gastric acidity
Gastric Acidity:
WA:
WB:
WA - efficently absorb by stomach
WB: absorbed in intestines
What are some things that affect drug absorbtion
changes in intestinal motility/pH/inflammation/food/other drugs
T/F morphine slows GI motility
true
Describe drug distribution
hint:movement of drug…
movement of a drug between blood circulation/tissues/organs and the relative proportion of drug in tissues
T/F Free fractions can not diffuse out of vasulature
False, they can diffuse out of the vasculature and into intersitial places
The ability to leave circulation depends on what?
Hydrophobic
Polar
Ionized
Lipid solubility
High hydrophobic - easily cross
Polar can cross but dont enter
Ionized diffuse out of vasculature but slowly
Volume of distribution to drug concentration
Hydrophobic
Ionized
Hydrophobic has large vol Distrib
Ionized or primary protein has small volume
Briefly describe free vs bound drugs
Active fractions
most drugs are subject to binding w serum protein (Drug-protein complex)
Only free/unbound can interact with site of action/bioresponse (Active fraction)
Briefly describe Standard dose
total plasma concentration within T.R, adverse effects w/ free fraction or no therp benefit to low free fract
T/F changes in active fractions may not occur secondarily to changes in plasma protein concentration
False
Describe ALB
majority of
major..
majority of plasma protein const.
major transporter of blood
T/F free fractions are influenced by other drugs
True
T/F measurement of free fractions shouldn’t be considered when drugs are highly bound/or have clinical signf inconsistences
False