Mata- Principles of Toxicology Flashcards
what are the top five agents involved in drug-related deaths?
cocaine, opioids, benzodiazepines, alcohol, antidepressants
what determines a drugs dose?
route, duration/ frequency of exposure and chemical properties
what type of response is measured, in order to determine the median toxic or lethal dose of a substance?
Quantal dose-response. (Graded response refers to the individual)
how is the therapeutic index (TI) calculated?
LD50/ED50
if an “on-target” drug goes to an unintended tissue what happens?
goes to correct receptor but its in the incorrect tissue. this means the high dose will lead to chronic activation or inhibition effects
how do you intervene to prevent or reduce toxicity after exposure?
reduce absorption of toxin, reduce or increase metabolism, increase excretion of toxin, neutralize toxic effects
what is activated charcoal used for?
to help in intervention of certain toxins, by effectively adsorbing them
why is it bad if acetaminophen reacts with P450?
quinone intermediate is created and damages the liver
fomepizole is the antidote in methanol and ethylene glycol. how does it work?
competitively inhibits the alcohol dehydrogenase which breaks down methanol and ethylene glycol
how does ion trapping help in renal elimination?
renal clearance can be enhanced by increasing urinary pH
competitive antagonists are used to neutralize the toxic effects of xenobiotics. what does it prevent?
prevents binding of toxin with its target site, prevent binding endogenous chemical with its target site
in opioid toxicity, naloxone is used to treat it. how does it work and how is it administered?
pure competitive antagonist that is administered via IV
in lead poisoning, 99% binds to what? and what organ clears it from the body?
erythrocyte and kidney
chelation therapy is used to treat patients that are experiencing tremors, inflammation of the gums, renal toxicity and psychiatric symptoms. what is chelation therapy treating?
mercury poisoning
