therapeutic drugs/toxicology Flashcards
(54 cards)
the analysis, assesment, and evaluation of circulating concentrations of drugs in serum, plasma, whole blood
therapeutic drug monitoring
therapeutic drug monitoring is often ordered with what other tests
creatinine, BMP, CMP, hepatic function panels
why do we do TDM
to assess drug dosages and see if drug is effective
advantages of TDM
- identifying non-compliant patients
- maximizing therapeutic effect
- optimizing a dosing regimen based on drug-drug interactions
mechanism of action for TDM
- interaction of a drug at its receptors/targets
- drug+receptor–> drug receptor complex –> effect
factors that effect drug effect and dosage
- age
- weight
- tolerance
- rate of elimination
- time of administration
- genetic factors
- metabolism of other medications
- protein binding
- disease states
- medication errors/compliance
involves the dynamics associated with movement of drugs across cell membranes
Pharmacokinetics
5 pharmacological parameters
- liberation (route of admin)
- absorption
- distribution
- metabolism
- excretion
only ___ fraction of drugs can interact with site of action, resulting in biologic response
free fraction
routes of administration
- injection
- inhaled
- absorbed
- rectal
- oral
routes of injection administration
- circulation (IV)
- muscles (IM)
- Skin (subcutaneous)
- epidermal
rate at which drug leaves the site of administration and the extent to which this happens
absorption
mechanism of absorption
passive diffusion, active transport
the fraction of a drug that is absorbed into systemic circulation
bioavailability
dristribution of drugs
- blood flow
- capillary permeability (pH gradients, lipid solubility)
- binding of drugs to proteins (free form reacts with receptor)
biotransformation of the parent drug molecules into one or more metabolites by enzymes
metabolism of drug
converts hydrophobic substances into water soluble, which are then transported into bile or released into circulation
MFO, hepatic mixed function oxidase
major enzymes that metabolize drugs
Cytochrome P450
interactions that can alter drug processes
drug-drug
drug-food
drug-beverage (alcohol/caffeine)
effectiveness of a drug over a population
Pharmacogenomics
patients benefitting from therapeutic and desired effects of drug
responders
patients not benefitting from therapeutic/desired effects of drugs
non-responders
gene group family that affects drug metabolism, functions in oxidizing drugs
Cytochrome P450
rate of change of drug concentration over time varies continuously with the concentration of the drug
elimination
