Toxicology

Question 1

what are the primary determinants of toxicity?

Answer 1

1. dose (main determinant)

2. time

Question 2

who is the father of modern toxicology & said that the right dose differentiates a poison & remedy?

Answer 2

Paracelsus

Question 3

what is the LD50?

Answer 3

lethal dose at which 50% of animals dies

Question 4

what is the legal definition of a poison?

Answer 4

LD50 under 50 mg/kg bwt

Question 5

tx index?

Answer 5

LD50/ED50–>the larger the #, the safer the drug

Question 6

what is ALD?

Answer 6

average lethal dose: estimated from accidental deaths in humans

Question 7

steps in clinical management of poisoning

Answer 7

1. ABC

2. reduce drug in body to decr time of exposure

Question 8

if tx’ing an unconcsious patient that you think may have OD’d?

Answer 8

1. glu if suspect hypoglycemia
2. insulin if suspect diabetic shock
3. naloxone if suspect narc OD

Question 9

what are toxidromes?

Answer 9

known toxicology standards

Question 10

what can be used to induce emesis?

Answer 10

1. apomorphine

2. syrup of ipecac

Question 11

how does charcoal work to reduce toxicity in body?

Answer 11

large SA–>toxicants bind–>prevents absorption of these toxicants

Question 12

what component do chelating agents typically have?

Answer 12

sulfates–>bind the heavy metal

Question 13

how to tx lead poisoning

Answer 13

DMSA

Question 14

what is the drug of choice for ethylene glycol or methanol toxicity?

Answer 14

fomepizole

Question 15

cherry red appearance of the lips and gums

Answer 15

COHb 40-60%

Question 16

what is the antidote for too much warfarin?

Answer 16

vitamin K (phytonadione)

Question 17

what is the antidote for methemoglobinemia?

Answer 17

methylene blue

Question 18

MOA: tx causes a direct chemical reduction of methemoglobin back to hgb

Answer 18

methylene blue

Question 19

what are toxidromes?

Answer 19

well characterized clinical syndromes that provide a sx fingerprint for assc’d intoxicants

Question 20

hallucunations, paranoia, mydriasis, HTN, tremor, hyperthermia

Answer 20

cocaine, amphetamines, PCP

Question 21

coma, decreased respiration, miosis or mydriasis, hypotension

Answer 21

alcohol, barbituates, benzos

Question 22

coma, respiratory depression, pinpoint/miosis, hypothermia, hypotension, histamine release

Answer 22

opioids

Question 23

what is the opiate triad?

Answer 23

hypothermia, hypotension, histamine release

Question 24

agitation, mydriasis, fever, sry skin, flushing, urinary retention

Answer 24

anticholinergics, antidepressants

Question 25

fasciculation, incontinence, salivation, wheezing, lacrimation, bradycardia

Answer 25

organophosphates, nicotine

Question 26

coma, agitation, mydriasis, dysrhytmia, convulsions, hypotension

Answer 26

TCA

Question 27

incr respiration, diaphoresis, tinnitis, agitation, alkalosis (early), acidosis (late), hyperpyrexia

Answer 27

salicylates, ASA,

Question 28

Dilated pupils due to antimuscarninic effects, increased HR

Answer 28

meperidine (opioid with diff effects than others)

Question 29

what to use to tx benzo OD?

Answer 29

flumazenil

Question 30

what is the most potent poison known?

Answer 30

botulism

Question 31

how to tx cyanide poisonin (3 steps)

Answer 31

1. inhale amyl nitrate 2. IV sodium nitrate 3. IV sodium thiosulfate

Question 32

which component of cyanide antidote: oxidize a portion of Hb iron from ferrous state to ferric state, converting Hb to methemoglobin

Answer 32

nitrates (step 1-2)

Question 33

which component of cyanide antidote: react with cyanmethhemoglobin to give thiocyanate & Hb?

Answer 33

sodium thiosulfate (step 3)

Question 34

what can be a lifesaving adjunct for methanol and ethylene glycol poisoning?

Answer 34

hemodialysis (esp use in patients who are sx)

Question 35

what is the drug of choice for methanol and ethylene glycol poisoning?

Answer 35

fomepizole

Question 36

how to tx acetaminophen toxicity?

Answer 36

n-acetylcysteine