Principles of toxicology

Question 1

Teratogenesis is the

Answer 1

creation of birth defects

Question 2

A teratogen is a

Answer 2

substance that can induce birth defects

Question 3

The teratogenic effect of any substance depends on

Answer 3

the developmental timing of the exposure

Question 4

What are the four manifestations of deviant development

Answer 4

Functional deficit
growth retardation
malformation
Death

Question 5

What period of organogenesis is teratogens most potent

Answer 5

b/t 3rd & 8th weeks of gestation

Question 6

What is the most common preventable cause of mental retardation

Answer 6

fetal alcohol syndrome

Question 7

What is the best way to prevent further absorption of a toxic compound

Answer 7

eliminate exposure

Question 8

Ipecac syrup works by

Answer 8

irritating G.I tracts

activating CTZ

Question 9

Apomorphine is a

Answer 9

dopamine agonist that works directly on CTZ

Question 10

Inhibiton of toxication involves

Answer 10

inhibiting the enzymes involved in metabolizing xenobiotics into its toxic product

Question 11

Name two competetive inhibitors of alchohol dehydrogenase

Answer 11

ethanol

fomepizole

*alcohol dehydrogenase is the enzyme involved in converting alchohol into toxic aldehydes

Question 12

Enhancement of metabolism is used to tx toxicity by

Answer 12

accelerating metabolism of a toxic substance by inducing the appropriate p450 system

Question 13

Name an example of enhancement of metabolism

Answer 13

cyanide poisoning and treatment with amyl nitrite, sodium nitrite, and sodium thiosulfate

Question 14

Name five heavy metal chelators

Answer 14

edatate disodium
dimercaprol
succimer
deferoxamine
penicillamine/trientine

Question 15

edetate disodium tx what metal poisoning

Answer 15

lead

• L.E.D

Question 16

deFEroxamine tx what metal poisoning

Answer 16

iron

Question 17

peniCillamine/trientine tx what metal poisoning

Answer 17

copper

Question 18

Antivenins are

Answer 18

antibodies aganist venoms

Question 19

One danger with using antibodies as inctivators include

Answer 19

serum sickness

*typer III hypersenstivity rxn

Question 20

Define xenobiotics

Answer 20

principles of toxicology as they pertain to the behavior of foreign substances

Question 21

Xenobiotics are modified by phase I/phase II rxn, what are three possible changes

Answer 21

detoxification-rendered less toxic

toxic xenobiotic»converted to another toxic

toxication»harmless xenobiotic»toxic

Question 22

What are the four mechanisms of toxicity

Answer 22

Large molecular damage (protein, lipid,carbs)

Reactive species (ROS)

Inflammatory and immune mediated

Enzyme and receptor mediated

Question 23

What is apoptosis

Answer 23

failure of cellular repair mechanism resulting in shrinkage, nuclear condensation and formation of apoptic bodies

*just individual cell affected

Question 24

What is necrosis

Answer 24

enzymatic digestion of cellular contents, denaturation of cellular proteins and disruption of cellular membrane»inflammatory attracting cells»nearby damage to healthy cells

Question 25

Following cellular damage, a target organ system can respond in three ways

Answer 25

regenerate not regenerate form cancer cells

Question 26

Name three genes involved in carcinogenesis

Answer 26

proto-oncogens tumor suppressor genes tumor promoters

Question 27

List 4 toxicokinetic-based treatments to minimize patient harm

Answer 27

Prevention of absorption (ipecac syrup) Inhibition of toxication (ethanlol) Enhancement of metabolism (Mucomyst) Enhancement of elimiation (hemodialysis)

Question 28

List two types of poison inactivators

Answer 28

Heavy metal chelators antivenins

Question 29

There are four pharmacologic treatment of toxin ingestion. List and describe them

Answer 29

Pharm Antagonism----Naloxone Pharm enhancement of body fx----physostigmine Active Site Restoration---methylene blue for methemoglobinemia Metabolic pathway alternatives----vitamin K tx for warfarin poisioning