Specific Drug Induced Toxicities Flashcards
Acetaminophen symptoms
overdose when higher than 4 gm in 24 hr
early tox: anorexia, nausea, vomiting
24-48 hrs- elevated PT, increased transaminase levels
48 hr to 7 days- inc intracranial pressure, hepatic encephalopathy, coma, multiorgan failure
hepatic necrosis
Acetaminophen tx
gastric lavage with charcoal
give metoclopramide to prevent vomiting
acetylcystein (NAC) within 8-12 hrs of exposure to increase glutathione - adjust dose based on normogram
IV glucose for hypoglycemia
salicylates symptoms
phase 1: respiratory alkalosis- hyperapnea, inc O2 consumption and CO2 production
metabolic acidosis (later stages)- accumulation of salicylic acid, impariment of renal excretion of acids, depletion of bicarbonate reserve
hyperpyrexia
tinnitis and dizziness
salicylates tx
perform gastric lavage
blood sample for salicylate levels and acid-base studies
correct hyperthermia by external cooling
mechanical ventilation for resp depression
fluids containing glucose and electrolytes
sodium bicarb to alkalize urine and promote excretionn
treat coma with osmotic diuretics
dialysis if renal fxn is impaired
Cocaine, amphetamines, phencyclidine symptoms
sympathomimetics
CNS stimulation, muscle rigidity, seizures (with MDMA, methamphetamine, ecstasy) vtach or vfib severe htn coma death
sympathomimetics tx
cocaine, amphetamines, phencyclidine
maintain airway and resp
convulsions controled by diazepam
activated charcoal and remove contents of stomach by lavage or emesis
succinylcholine if convulsions interfere with resp
maintain bp with fluids (not vasopressors because may be hazardous)
no beta blockers!!
opioids symptoms
toxic triad:
unconscious
pinpoint pupils
slow, shallow respiration
cyanosis, hypotension, spasms of GI tract, spasticity and twitch of muscles, death from resp depression within 2-4 may occur
opioid tx
maintain vital signs
naloxone is opioid antagonist- repeat doses bc of short duration of action
anticholinergics symptoms
dry as a bone red as a beet blind as a bat hot as a hare mad as a hater bowel and bladder lose tone loss vagal break- arrythmias, tachycardia
tx of anticholinergics
physostigmine
atropine if physostigmine becomes poisonous
1st gen antihistamines symptoms
CNS excitation may precede eventual CNS depression
drowsiness, tremors, disorientation, excitement, hallucinations, hyperthermia, tachy, convulsions, coma, difficult to treat
(symptoms similar to anticholinergics, don’t use physostigmine to treat though!)
tx of antihistamines 1st gen
maintain vital signs
activated charcoal
control convulsions with diazepam
TCA symptoms
anticholinergic effects
CV toxicit- arrhythmias, hypotension, abnormal cardiac conduction- torsades de pointe
seizures
Tx of TCA
sodium bicarbonate- maintain pH to reverse cardiac depressant
tx seizures with diazepam, pancuronium
supportive tx
beta blocker symptoms
overextension of pharmaceutical action- hypotension, bradycardia, cardiogenic shock, heart block,
Normal QRS (widening in high overdose sometimes)
bronchospasms in pts with preexisting asthma
hypoglycemia, hyperkalemia
convulsions, coma,resp arrest
beta blocker that can cause QT prolongation and torsades, treatment for that
sotalol
isoproterenol infusion
magnesium
overdrive pacing
beta blocker tx
glucagon for bradycardia and hypotension
wide complex conduction defects can respond to sodium bicarb
serotonin syndrome
SSRIs, and in combo with MAOIs, TCAs, lithium, etc.
altered mental status,fever, agitation, myoclonus, hyperreflexia, ataxia, incoordination, drowsinessm shivering, diarrhea, diaphoresis
(looks like cocaine, lithium thyroid storm)
serotonin syndrome tx
supportive
cyproheptadine- serotonin antagonist
dantrolene
propranolol
alcohols and glycols
ethanol- hepatic, neuro, other systems
methanol- neurotoxic, ocular toxicity
isopropyl alcohol- cns depression, metabolized to acetone, renal damage, gastric lavage, treat symptoms
ethylene glycol and diethylene glycol- nephrotoxic
propylene glycol (generally regarded as safe)- used as vehicle for drugs
fomepizole
inhibits alcohol dehydrogenase
disulfiram
inhibits aldehyde dehydrogenous
increase acetaldehydes- causes hangover symptoms
ethanol symptoms
stimualtion due to inhibition of cns inhibitory (GABA) pathways- disinhibition
visual impariment, muscular incoordination, euphoria
diuresis by adh inhibition
inc salivation and gastric secretion
peripheral vasodilation , flushed skin,
acute ethanol poisoning
50-150%
dec inhibitions, visual impariment, slow rxn time
moderate ethanol poisoning
major visual impairment, slurring of speech
severe ethanol poisoning
convulsions, fatalities, severe hypoglycemia, approaching stupor
coma in ethanol
unconsciousness, slowed resp, loss of sesnsations, death
BAC 500%
fetal alcohol syndrome
small head, undeveloped pinna, short nose, missing groove above lip, pointed small chin, small eye opening, flat face, thin lips
ethanol tx
acute- support, avoid depressants
chronic- diazepam, prevent withdrawal during tx program with chlorodiazepoxide, addiction counseling
disulfiram to discourage alcohol use
naltrexone- opioid antagonist in treating alcohol addiction
acamprosate- analog of GABA and homotaurine, maintenance of abstinence
methanol poisoning
blindness!
death due to acidosis and resp failure
acute toxicity of methanol results from rapid metabolic conversion to formaldehyde and formic acid
methanol tx
emesis
50% ethanol IV (bc methanol and ethanol compete for alcohol dehydrogenase ethanol will decrease formation of toxic metabolites)
fomepizole
treat acidosis with sodium bicarb
ethylene glycol and diethylene glycol symptoms
similar to ethanol
kidney damage to due to calcium oxalate crystals
ethylene glycol tx
gastric lavage
give ethanol IV
fomepizole
