Toxicology
Cosmetics generally safe (exceptions are wave neutralizer [boric acid] an nail products [acetonitrile, methacrylic acid, nitromethane)
Cleaning substances toxic when concentrated (Drano contains 54% NaOH)
Plants are variable (Philodendrons contain calcium oxylate crystals causing pain, Foxglove contains digoxin causing side effects)
Pharmaceuticals DUH!, most frequent are analgesics and cold/cough medicines, Pediatric fatalities often due to excessive iron intake
Toxin
MOA
Effects
Treatment
Miscellaneous
Carbon Monoxide binds to hemobglobin tissue hypoxia, 30-50% HA, faint on pure or hyperbaric
product of incomplete combustion
240X stronger than
exertion, irritability, dizziness
oxygen
shift oxygen dissoc. curve to left
oxygen
thus lowering partial pressure of
collapse; 60-70% cause  HR, CO,
oxygen availability to tissues,
RR, Pinkish skin discoloration
Sulfur Dioxide
form acid w. contact increased mucous,
remove exposure and
mucous membrane
bronchoconstriction
treat irritation
Nitrogen Oxide
pulm. edema, ENT irritation
reduce edema/inflam
from silage, gas/kerosene heaters
Ozone
treat
pulm
edema
and
prod by UV absorption by NO2
[low] = shallow rapid resp, pulm
inflammation
compliance, [high] = pulm edema,
bronchitis, bronchoconstrictor sens
Arsenic
interacts with
Acute = PAIN, corrosion of GI
supportive,
colorless and tasteless, found in
tract, bleeding, irritant, vomiting,
Dimercaprol
industry, herbicides, insecticides,
sulfhydryl groups
(pyruvate deh. in
“rice water” stool and death,
natural in ground water, burnt coal
TCA cycle)
Chronic = hyper-pig and -ker, cancer
(skin, lung, bladder), alopecia, BM
depression, anemia
Cadmium
inhibits sulfur cont
Inhalation = Pulmonary edema +
Vitamin D, supportive, manufacturing, burnt fossil fuel,
enzymes (esp. AAT) Nephrotoxicity, Oral =
poorly absorbed from GI tract
chelators ineffective
osteomalacia via bad Ca/PO4
balance (bone pain)
Lead
bind sulfhydryl group can replace Ca in bone (reversible),
EDTA, Dimercaprol,
children, lead based paints
(inhibit ALA
Acute = RARE, encephaloacolic,
Penicillamine,
dehydratase causing colic, Chronic = periph neuropathy,
Succimer (children),
recommended when
anemia,
neurocognitive
defects
heme synthesis)
(children), growth retardation
conc >45 ug/dL
Mercury
bind sulfhydryls,
Acute = chest pain SOB, N/V,
Penicillamine,
CNS and kidney are target
phosphoryl, carboxyl, Chronic = CNS, tremors, emotional
Dimercaprol, ineff. for organs, Methyl mercury is most
amide, amines
fx, irritability, Mad Hatter
methyl mercury
toxic form
syndrome
Iron
occur when Fe<
corrosive on GI tract, ulceration,
prevent additional
iron overload from vitamins
binding cap of
absorption via ipecac
(children), iron rapidly cleared
hemorrhage, coag necrosis, CO,
ferritin,
induced emesis,
from plasma
shock, hepatic damage, bloody
Toxin
Ethanol
MOA
Methanol
Ethylene Glycol
 ox phos, cell resp,
and glucose metab
Hydrocarbons
many
Atropine
Antimuscarinics
Cholinomimetics
OP inhibitors of
AChE, Carbamate
Opiods
Heroin, Morphine
Salicylates
uncouple ox phos
SedativesHypnotics
Barbiturates,
Ethanol,
Benzodiazepines
Cocaine,
Amphetamines
Stimulants
Tricyclic
Antidepressants
Acetaminophen
Fast Na channel
block, inotropism
NAPQI reactive
diarrhea, tachycardia, hepatic
failure, SGOT, SGPT
Effects
visual impairment, alcoholic
ketoacidosis
greatest acidosis of alcohols, glycols,
or aldehydes, permenant blindness,
metabolic acidosis, CNS depression
(euphoria, weakness, coma,
convulsions), fixed dilated pupils,
Ca oxalate crystals damage tissues
leading to pulm edema, CHF,
tachycardia, renal failure
gastric lavage,
Deferoxamine
Treatment
symptomatic
CNS depression, pneumonitis,
edema, hemorrhagic
bronchopneumonia,
delirium, hallucinations, seizures,
coma, tachycardia, HTN,
hyperthermia, mydriasis
Anxiety, agitation, seizures, coma,
brady or tachycardia, pinpoint
pupils, salivation, sweating (SLUD)
Lethargy, sedation, coma, cool skin,
bradycardia, hypotension,
hypoventilation, pinpoint pupils
anion gap metabolic acidosis,
lethargy, seizures, hypokalemia,
dehydration, hyperthermia
hypotension, hypothermia,
nystagmus, decreased muscle tone
prevent aspiration
ANS modulation (vasoconstriction,
myocardial stimulation), ventricular
arrythmias and hypotension
widened ORS complex, CCC
(coma, convulsion, cardiotoxicity
No immediate effects short of N/V
control seizures, BDZ,
control
hypterthermia
Diazepam (seizures),
Phenytoin (arryth)
N-Acetyl Cysteine
Emesis, Lavage,
Ethanol, Fomepizole ,
Na-bicarb with major
focus being correction
of acidosis
Ethanol, Na Bicarb,
hemodialysis,
Fomepizole
Miscellaneous
preferentially metabolized in
presence of Methanol
toxicity via metabolism to
formaldehyde and formic acid,
ELEVATED ANION GAP
ACIDOSIS
toxicity via metabolism to oxalic
acid, sweet taste, toxic doses as low
as 100 mL, LARGE ANION GAP
ACIDOSIS
no emesis unless ingestion exceeds
1mL/KG or if contains metals,
camphor, or insecticides
Physostigmine but not
with TCAs, control
hyperthermia
support respiration,
Atropine, Praloxidime
Naloxone, support
respiration
alkalinize urine,
potassium, Na bicarb
Flumenazil for BDZ
myocardial toxicity treated with
hypertonic Na bicarb
reduced GSH primary reason for
intermediate forms
and malaise, Hepatotoxic w. death
adducts
in 7-10 days
Anion Gap (for this class) is (Na + K) – (HCO3 + Cl) which should normally be 12-16 meq/L
toxicity
Treatment of Intoxication
Chelators bind and stabilize metals, are water soluble (Renal excretion), often administered in Ca form (since will complex endogenous Ca)
Drug
MOA
Use
Side Effects
Miscellaneous
Dimercaprol
chelator
acute Arsenic and Mercury, NOT
not cure neurological effects,
tachycardia, HTN, N/V,  PT
Cadmium and Iron
Parenteral admin
Calcium Disodium chelator
Iron, Lead, Zinc
Nephrotoxicity (avoid in RTN) IV admin, minimize toxicity with
Edetate (CDE)
hydration and <5 day treatment
Penicillamine
chelator
Copper, adjunct for Gold, Lead,
can be severe including
well absorbed after oral admin
and Arsenic, long term treatment nephrotoxicity, lupus, hemolytic
after acute Dimercaprol (Mercury) anemia
or CDE (Lead) treatment
Deferoximine
chelator
acute Iron
urticaria, neurotoxicity,
Parenteral
hepatic/renal, rapid IV admin
cause histamine release and
hypotensive shock
Succimer
chelator
DOC for Lead, also Arsenic and
less toxic than Dimercaprol,
higher TI and more water soluble
Mercury if given immediately
than Dimercaprol
rash, CNS, liver enzymes
Ipecac
Emetic
prevent absorption of Iron
Ethanol
Competitor
Ethylene Glycol or Methanol
Anti-alcohol dehydrogenase
Fomepizole
Inhibitor
Methanol or Ethylene Glycol
Anti-alcohol dehydrogenase