Toxicology Flashcards
Aspirin MOA
uncoupling of oxidative phosphorylation –” icnreased Co2
icnreased heat production
ketone bodies
increased pyruvate and lactate
symptoms of aspirin
n/v, fever, tachypnea
fluid loss and dehydration
tinnitus
mixed resp alklaosis and increased anion gap metabolic acidosis
death from aspirin = ?
respiratory failure due to central respiratory paralysis
tx of aspirin
IV sodium bicarbonate = acidosis and at severe - hemodialysis
acetaminophen death?
fulminant liver failure – hepatic encephalopathy and death
tx of acetaminophen?
NAC and liver transplant with fulminant hepatic failure
list the amphetamines and other stimulants
end in E
methamphetaminE methylenedioxymethamphetaminE cocainE pseudoephedrinE ephedrinE phenylpropanolaminE
sxs of amphetamines and stimulants at usual doses
euphora
wakefulness
sense of power
sense of well being
sx of amphetamines and stimulants at higher doses
agitation
acute psychosis
o/d of amphetamines and stimulants = ?
tachyarrhtymias
seizures and muscular hyperactivity – hyperthermia and rhabdomyolsis
~~~pupils dilated with warm and sweaty skin
amphetamines and stimulants
treatment of amphetamines and other stimulants
symptomatic only. no specific antidote
- ammonium chloride* acidification of urine
- phentolamine or nitroprusside - HT
- propanolol or esmolol - tachyarrhthymias
- benzos - seizures
List drugs that have anticholinergic effects
anticholinergics
antihistamines
antidepressnats TCAs
antipsychotics
a/se of antihistamines
anticholinergic – seizures
a/se of TCAs
anticholinergic – CV toxicity
typical presentation of anticholinergic
red as a beet - skin flushed
hot as a hare - hyperthermia
dry as a bone - no sweating and dry mucous membranes
blind as a bat – blured vision, cyclopledia, pupillary dilation
mad as a hatter - condusion delirium, tachycardia
treatment of anticholinergics
pysostigmine
treatment of TCA overdose
so not give physostigmine bc will aggravate cardiotoxicity
most toxic beta blocker
propranolol bc at high doses it blocks Na channels
lipophilis and enters the CNS causing seizures and coma
sx of beta blocker
bradycardia
hypotension
seizures and cardiac conduction block bc lipophilic and blocks Na channels
tx of bb blocker
IV glucagon – increases cAMP
CCB overdose
Ca IV
glucagon
epinephrine
to icnreased BP at refractory hyptension
symptoms of TCA
antag at muscarnic - mad, hot, blind, dry
alpha blockers - vasodilation
quinidine like depressnat at heart - block na channels - slow conduction and depress contractility
treat TCA overdose
NE for hypotehsnion and sodium bicarbonate
MAOi symptoms
severe hypertension reactions when with tyramine foods or drugs like phenylpropnaolamine or ephedrine
treat MAOi
phentolamine or labetolol
what is serotonin syndrome
MAOI with a serotenergic agent –> overstimulation with 5HT1a and 5HT2 receptors
sxs of serotonin syndrome
hyperthermia
muscle rigidity
myoclonus
hyperreflexia
treatment of serotonin syndrome
cyproheptadine 5HT2 antag
benzos - rigidity, serizures, agitation
Neuroleptic malignant syndrome caused by
antipsychotics
sx of neuroleptic malignant syndrome
muscle ridigity hyperthermia metabolic acidosis confusion FEVER F: fever E: encephalopathy V: vitals unstable E: elevated enzymes R: rigidity of muscles
tx of neuroleptic malignant syndrome
bromocriptine and dantroline
O/d sxs of opioids
letaryg
small pupils
bp and pulse decrease
higher dose o/d opioids
coma
respiratory depression
apnea
treatment of opioids
maintain vitals
naloxone
nalmefene
what is the most common side effect of sulfonylureas and meglitinides?
hypoglycemia
how to treat sulfonylureans and meflinitides
glucose bolus
IV octretoide - antagonizes insulin release
OR
diazoxide - antagonize insulin release
CO + Hb
carboxyhemoglobin
LEFT SHIFT
sx of Co poisoning
headache and tightness in temporal region
death - respiratory paralysis
tx of CO
100& O2 hyperbaric
Ethanol sxs
disinhibition, lethary, ataxia, impaired judgement, stupor, coma, death
ethanol signs
hypoglycemia
hypothermia
increased anion gap metabolic acidosis
tx ethanol
prevent aspiration
thiamine
IV dextrose
correct electrolytes
Methanol is found where?
paint solvent
photocopying fluid
windshield washing fluid
what is methanol metabolized to?
formaldehyde
consequences of methanol
acidosis
retinal damange
blindness
death - sudden cessation of respiration
tx of methanol
ethanol @ oh dehydrogenase
fomepizole - inhibits alcohol dehydrogenase
bicard
hemodialysis
Ethylene glycol source
antifreeze
ethylene is metabolized to?
aldehydes adn oxalate
consequences of ethylene
severe acidosis
renal dmage
treatment of ethylene
ethanol
fomepizole
a high osmolar gap suggests poisoning with?
methanol
ethylene glycol
toxicity from cholinesterase inhibitors found @ whom?
suicidal
work exposure
terrorist attack
sxs of muscarinic overactivation like organophosphates
DUMBELS: D - diarrhoea U - urination M - miosis B - brady cardia an dbronchoconstriction E - emesis L - lacrimation S - salivation and sweating
signs of nicotinic overactivation @ organophosphates
hypertension, tachy or brady
muscle twicth and fasiculations
most common cause of death is resp paralysis
treatment of organophosphates
atropine and pralidoxime
treatment of carbamate insecticides
atropine only bc short lived and spontaneously reversible no pralidoxime
sources of cyanide
plastic, jewelry, wool, silk, cassave and apricot seed
cause of death @ cyanide
respiratory arrest
MOA cyanide
high affinity for Fe3+ – binds heme of cytochrome a, a3 = O2 cant act as final acceptor in the ETC – CYTOTOXIC HYPOXIA - lactic acidosis
treatment of cyanide
provide a large pool of ferric iron to compete for cyanide
compnent of cyanide antidote kit
amyl nitrite pearls
sodium nitrite
sodium thiosulfate
how do the components of the cyanide antidote kit work?
nitrites oxidze Hb to methemoglobin (prilocaine) –> forms cyanmethemoglbin and cytochrome oxidase is restored
how does thiosulfate help cyanide antidote style?
thiosulfate donates sulger that then makes cyanmethemoglobin thiocyante and methemoglobin by rhodanese –> pee out thicyanate
what does methylene blue do?
restores methemoglobin to ferrous form
how does hydroxocobalamin help wtih cyanide poisoning?
reacts with cyanide to yield cyanocobalamin (precursor of B12)
better because no metemoglobin
source of lead
ammunition
lead miners
battery manufacturers
lead containing pain
sx of acute lead poisoning
abdominal colic and CNS changtes
sx of acute lead poisoning
plumbism
peripheral neuropathy - tremor, anaemia, anorexia, weight loss gi symptoms
normocytic/microcytic and hypochromic anaemai
delta ALA dehydratase and ferrochetlase
a
treat lead poisoning
diazepam - seizures
mannitol and dexamethasone - cerebral oedema
chelation - EDTA , dimercaprol siccimer
What are you treating? diazepam, manntiol, dexamethasoen, EDTA, dimercaprol, succimer
lead poisoning
arsenic
contaminated wine or moonshine and water of fodo contamination - shell fish and other seafood
i say diarhhoea ricewater stools and sweet garlicky breath
acute inorganic arsenic poisoning
sx or arsine gas
massive hemolysis
sxs of chronic organic arsenic poisonings
skin changes
cancer
RAINDROP
MOA arsenic
trivalent react wtih SH
uncouple oxidative phosphoylation
hemolysis by depleting glutathione in the rbc
tx of arsenic
unithiol
dimercaprol
MOA mercury
SH groups
source of mercury
battery
thermometer
barometer
fish
symptoms of mercuric chloride
corrosive - hemorrhagic gastroenteritis
symptoms of chronic meurcry poisoning
classic triad
1) tremor
2) neuropsychiatric disturbances
3) gingivostomatis
mercury poisoning in children
acrodynia
painful erythemia
mil
treatment of mercury
unithiol and succimer
DO NOT USE DIMERCAPROL
iron symptoms
vomiting gi bleeding lethardy GRAY CYANOSIS gi necrosis
treatment of iron
deferoxamine
