BMB 3 - Toxidromes & Antidotes Flashcards
What do ED50, TD50, and LD50 stand for in terms of a particular pharmacologic agent?
Effective dose 50
Toxic dose 50
Lethal dose 50
What is the ED50 for a pharmacologic agent?
The dose at which 50% of individuals experience the therapeutic effect
What is the TD50 for a pharmacologic agent?
The dose at which 50% of individuals experience toxicity
What is the LD50 for a pharmacologic agent?
The dose at which 50% of individuals are killed
How is the therapeutic index calculated for a particular pharmacologic agent?
TD50 / ED50
Which is safer, a high therapeutic index or a low therapeutic index?
High
(TI = TD50 / ED50)
(Higher TIs indicate a larger gap between toxic dosing and the lower doses at which efficacy is achieved.)
Management of drug toxicities, overdoses, etc. should always start with what three things?
The ABCs
Airway
Breathing
Circulation
A patient presents in an apparent coma. What should you administer?
Glucose
Insulin
Naloxone
(thiamin?)
A patient presents while seizing.
What should you administer to stop the seizure?
Diazepam
A patient presents with severe agitation.
What should you administer?
An anxiolytic
In order of importance, name the three main laboratory methods for determining the cause of a poisoning.
- Urine (first choice)
- Blood/serum (second choice)
- Gastric contents (third choice)
A patient presents with lead poisoning.
What do you administer?
Dimercaprol
or
penicillamine
A patient presents with arsenic poisoning.
What do you administer?
Dimercaprol
A patient presents with mercury poisoning.
What do you administer?
Dimercaprol
or
penicillamine
A patient presents with iron poisoning.
What do you administer?
Deferoxamine
A patient presents with copper poisoning.
What do you administer?
Penicillamine
A patient presents with heparin toxicity.
What do you do?
Administer protamine sulfate
A patient presents with botulinum toxicity.
What do you do?
Administer antitoxin
+
provide respiratory support
A patient presents with organophosphate poisoning.
What do you do?
Administer atropine + pralidoxime
A patient presents with cyanide poisoning.
What do you do?
Administer amyl nitrate
(subsequent thiosulfate can increase excretion)
A patient presents with ethylene glycol poisoning.
What substances can be used to prevent its conversion to toxic metabolites?
Ethanol
Fomepizole
A patient presents with methanol poisoning.
What substances can be used to prevent its conversion to toxic metabolites?
Ethanol
Fomepizole
A patient presents with carbon monoxide poisoning.
What do you do?
Administer hyperbaric O2
A patient presents with warfarin toxicity.
What do you do?
Administer fresh frozen plasma + vitamin K
A patient presents with opiate overdose.
What do you do?
Administer naloxone
(and subsequent naltrexone)
A patient presents with curarine poisoning.
What do you do?
Administer cholinesterase inhibitors
(to reverse the NMJ blockade)
A patient presents with methemogobulinemia due to nitrate poisoning.
What do you do?
Administer methylene blue
(to reduce Fe3+ to Fe2+)
A patient presents with methemogobulinemia due to sulfa drugs.
What do you do?
Administer methylene blue
(to reduce Fe3+ to Fe2+)
A patient presents with digitalis toxicity.
What digoxin-antibody can you administer?
Digibind
A patient presents with a 5-fluorouracil overdose.
What do you do?
Administer thymidine
A patient presents with anticholinesterase toxicity.
What do you do?
Administer atropine
A patient presents with agitation, mydriasis, seizures, and hypertension.
What toxidrome is on your differential?
Sympathomimetic use
(e.g. cocaine, amphetamines, PCP, etc.)
A patient presents with CNS depression, decreased reflexes, and hypotension.
What toxidrome is on your differential?
Sedative use
(e.g. alcohol, benzodiazepines, barbituates, etc.)
A patient presents with respiratory depression, hypothermia, pinpoint pupils, and hypotension.
What toxidrome is on your differential?
Opiate use
(e.g. morphine, codeine, heroin, etc.)
A patient presents with agitation, mydriasis, fever, dry skin, flushing, and urinary retention.
What toxidrome is on your differential?
Anticholinergic use
(e.g. atropine, scopolamine, TCAs, etc.)
A patient presents with coma, fasciculation, salivation, lacrimation, and wheezing.
What toxidrome is on your differential?
Cholinergic use
(e.g. organophosphates, carbamates, nicotine, etc.)
A patient presents with diaphoresis, tinnitus, early alkalosis, and late acidosis.
What toxidrome is on your differential?
Salicylate use
Describe the S/Sy of the toxidrome caused by overdose with the following:
Sympathomimetics
(e.g. cocaine, amphetamines, PCP, etc.)
Agitation,
mydriasis,
seizures,
hypertension
Describe the S/Sy of the toxidrome caused by overdose with the following:
Sedatives
(e.g. alcohol, benzodiazepines, barbituates, etc.)
CNS depression,
decreased reflexes,
hypotension
Describe the S/Sy of the toxidrome caused by overdose with the following:
Opiates
(e.g. morphine, codeine, heroin, etc.)
Respiratory depression,
hypothermia,
pinpoint pupils,
hypotension
Describe the S/Sy of the toxidrome caused by overdose with the following:
Anticholinergics
(e.g. atropine, scopolamine, TCAs, etc.)
Agitation,
mydriasis,
fever,
dry skin,
flushing,
urinary retention
Describe the S/Sy of the toxidrome caused by overdose with the following:
Cholinergics
(e.g. organophosphates, carbamates, nicotine, etc.)
Coma,
fasciculation,
salivation,
lacrimation,
wheezing
Describe the S/Sy of the toxidrome caused by overdose with the following:
Salicylates
Diaphoresis,
tinnitus,
early alkalosis,
late acidosis.
