absorption, distribution, excretion of toxicants

toxicokinetics

The study of how a substance gets into the body and what happens to it in the body “what we do to the drug”

toxicokinetics

refers to the molecular, biochemical, and physiological effects of toxicants or their metabolites in biological systems – what it does to the body

absorption

the transfer of a chemical from the site of exposure, usually an external or internal body surface, into the systemic circulation

distribution

is the movement of toxicants from systemic circulation by biotransformation, excretion, and storage at various sites in the body

excretion

the removal of xenobiotics from the blood and their return to the external environment via urine, feces, exhalation, etc.

the active form of that chemical

The toxic action of a chemical is a consequence of the physical/chemical interaction of _________ with a molecular target within the living organism

Effect of pH on the ionization of a compound

• changes how a drug may be absorbed or excreted

Henderson Hasselbach concept

first pass

The removal of chemicals before entrance into the systemic circulation is referred to as pre-systemic elimination

DDT

barium sulfate, ddt, acet

osmosis thrugh bone

which of the following is not major route?

carbon monoxide?

which binds to hemoglobin

passive and specialized transport

what are the two types of transport

between tight junctions

paracellular reabsorption

50%

if pH and pKa are equal, hoe much is ionized

ATP

what does active transport require?

ABC transporter

Which is ATP-dependent?

endocytosis

OATPs

which transporter family in liver and kidneys?

large surface area with appropriate pH

why is SI the biggest sight of absorption

elimination in GI tract

Henry’s

gas equilibrium equation

phgocytosis (by macrophages)

what removed inhaled particles from the lung

stratum

most important skin layer for absorption

nonionized

benzoic acid pKa is 4. what happens to it from pH 1-3?

ionized

at pH 7, benzoic acid is

highly lipophilic

new drug coefficient 100 (ethanol/water)