Exam 3 TDM/Toxicology

the analysis, assessment, and evaluation of circulating concentrations of drugs in serum, plasma, or whole blood

to ensure that a given drug dosage produces maximal therapeutic benefit and minimal toxic adverse effects

o Identifying non-compliant patients o Maximizing therapeutic effect o Optimizing a dosing regimen based on drug-drug interactions

Age, weight, tolerance, rate of elimination, time of administration, genetic factors, metabolism of other drugs, protein binding, disease states, medication errors/compliance

Liberation Absorption Distribution Metabolism Excretion

The release of the drug from its dosage form

Rate at which drug leaves site of administration and the extent to which this happens

the process by which drug diffuses or is transferred from intravascular space to extravascular space (body tissues) - blood flow, capillary permeability

o Transformation of the parent drug molecule into one or more metabolites by enzymes

– hepatic mixed function oxidase  Converts hydrophobic substances into water-soluble substances  Then transported to bile or released into circulation for elimination

o Rate of change of drug concentration over times varies continuously with the concentration o Functional changes in organs can affect rate of elimination (such as hepatic disease/cirrhosis – slows clearance)

• Injections – IV (fastest), intramuscular, subcutaneous, epidermal • Inhalation • Absorbed through skin (slowest) • Rectal • Oral

• Major enzymes that metabolize drugs * Gene group family that affects drug metabolism

the study of how a person’s unique genetic makeup (genome) influences his or her response to medications.

• Drugs administered through IV enter directly into systemic circulation • Drugs administered orally are first exposed to the liver and may be metabolized before reaching the rest of the body

• Hepatic metabolism • Renal filtration • Skin, lungs, mammary glands, salivary glands

Digoxin, lidocaine, quinine, procainamide

• Used to treat CHF • Draw peak levels 2 hours post dose • Allows for better cardiac muscle contraction and rhythm

Used to treat premature ventricular contractions

• Used to treat cardiac arrhythmias * Prevents arrhythmias, atrial flutter, fibrillation

• Used to treat cardiac arrhythmic situations • Affects cardiac muscle contraction • Often measured with NAPA (N-Acetyl procainamide)

Aminoglycosides, vancomycin

• Gentamicin, tobramycin, amikacin, kanamycin • Used to treat infections with gram-negative bacteria • Inhibits protein synthesis of the microorganism

nephrotoxic, ototoxic