14. Toxicology

Question 1

Describes the change in effect on an organism caused by differing levels of exposure to a stressor

Answer 1

Dose-response relationship

Question 2

Describes how a patient will process and eliminate a compound; changes throughout life

Answer 2

Pharmacokinetics

Question 3

Suitable specimens for alcohol analysis

Answer 3

Whole blood
Serum
Plasma

Question 4

Most common route of exposure in clinical setting

Answer 4

Ingestion

Question 5

Analytical method of acetaminophen measurement on automated analyzers?

Answer 5

Immunoassay (EMIT, FPIA)

Question 6

Main method of treatment for acetaminophen toxicity?

Answer 6

IV administration of N-acetylcysteine (NAC)

Question 7

Toxic compound of acetaminophen metabolism

Answer 7

NAPQI

Question 8

Most common analytical method for salicylate measurement is the ________ reaction

Answer 8

Trinder

Question 9

Ethanol RI

Answer 9

<= 2.0 mmol/L

Question 10

The decrease in mediator prostaglandin is responsible for acetaminophen’s _________ effect

Answer 10

antipyretic

Question 11

Reye’s syndrome is associated with which analgesic?

Answer 11

Aspirin (salicylate)

Question 12

Increased ___ and ___ are sensitive indicators of excess alcohol intake

Answer 12

GGT, MCV

Question 13

Specific urine test that would suggest isopropanol toxicity

Answer 13

Ketone positive (detection of acetone)

Question 14

Any agent that counteracts the effects of a poison

Answer 14

Antidotes

Question 15

Sealed alcohol analysis specimens are good for ____ days w/o loss of ethanol

Answer 15

14 days

Question 16

ADH inhibitor used in the treatment of alcohol poisonings

Answer 16

Fomepizole

Question 17

The decrease in prostaglandin production is responsible for acetaminophen’s _________ effect

Answer 17

analgesic

Question 18

Toxic metabolite of methanol metabolism

Answer 18

Formic acid

Question 19

Level at which 50% of population will experience adverse toxic effects

Answer 19

TD50

Question 20

Toxic range of salicylate

Answer 20

> 2.20 mmol/L

Question 21

The quantitative study of a toxicant’s disposition in the body of an affected person over time

Answer 21

Toxicokinetics

is the change in pharmacokinetic processes during a toxicological situation

Question 22

How does the Trinder reaction work?

Answer 22

Salicylate + Fe3+ = coloured complex

Question 23

3 treatments for salicylate toxicity

Answer 23

• Activated charcoal to bind aspirin
• Increase elimination - hemodialysis
• Correct acid-base, electrolyte disturbances

Question 24

This acid-base disorder occurs in early/mild salicylate poisoning

Answer 24

Respiratory alkalosis

Question 25

Property of aspirin that may cause prolonged prothrombin time (PT)

Answer 25

Interference w/ platelet aggregation

Question 26

3 main routes of exposure

Answer 26

Dermal Ingestion Inhalation

Question 27

What is LD50

Answer 27

Dose that would cause death in 50% of the population

Question 28

How does NAC help treat acetaminophen toxicity

Answer 28

Acts as glutathione substitute to help replenish hepatic glutathione = increases capacity of liver to detoxify the active metabolite (NAPQI)

Question 29

Therapeutic range of acetaminophen

Answer 29

70 - 130 umol/L

Question 30

Toxic range of acetaminophen

Answer 30

4 hrs after dose = >1324 umol/L 12 hrs after dose = >300 umol/L

Question 31

4 major disciplines within toxicology

Answer 31

clinical environmental forensic workplace/occupational

Question 32

Therapeutic range of salicylate

Answer 32

0.7 - 1.8 mmol/L

Question 33

Why does metabolic acidosis develop as salicylate poisoning progresses?

Answer 33

Salicylates: - enhance anaerobic glycolysis to cause excess production of organic acids - stimulates and mobilizes free fatty acids which convert to ketones

Question 34

ADH oxidizes ethylene glycol to?

Answer 34

Glycoaldehyde

Question 35

How is acetaminophen deactivated?

Answer 35

Conjugation w/ glutathione

Question 36

3 ways to treat methanol poisoning

Answer 36

- Give ethanol or fomepizole - Folate (enhance folate-mediated metabolism of formic acid) - Hemodialysis

Question 37

Why does ethylene glycol poisoning cause decreased Ca2+?

Answer 37

Ca2+ gets used in formation of calcium oxalate due to normal ethylene glycol metabolism

Question 38

What is TD50?

Answer 38

Threshold dose - level at which 50% of the population will experience adverse toxic effects

Question 39

What is ED50?

Answer 39

Effective dose - dose that would be effective/therapeutic in 50% of the population

Question 40

2 urine crystals seen in ethylene glycol poisoning

Answer 40

Calcium oxalate | Hippuric acid