Toxicology ( 5% ) Flashcards
Pt comes in staggering, agitated and hyperthermic with dilated pupils. Which is the least likely cause
- Atropine OD
- Amphetamines
- Angels trumpet
- TCA OD
- Aspirin OD.
Aspirin OD.
- Mydriasis = sympathomimetic (amphetamine) or anticholinergic (atropine, TCA)*
- Angels trumpet = anticholinergic (nightshade family)*
benztropine causes:
- miosis
- diarrhea
- confusion
- bronchorrhoea
- GI haemorrhage
causes anticholinergic symptoms constipation, mydriasis, less bronchial secretions, less GI blood flow
β blockers may cause drug interactions through a variety of mechanisms including all of the following except
- decreasing renal blood flow
- inducing cytochrome P450
- slowing the absorption of IM drugs by decreasing CO
- direct receptor binding site competition
- decreasing hepatic blood flow
OD of salicylates leads to all except
- Tinnitus
- Marked hyperventilation
- Increased metabolic rate
- N & V
- Metabolic alkalosis
Metabolic Acidosis
Following a respiratory alkalosis
Which is safe to use in TCA OD
- Phenytoin
- Flumazenil
- Quinidine
- Procainamide
- None of the above
Phenytoin
No interactions as per NZF (Greenlight)
- Flumazenil -> Risk of seizures
- Quinidine -> Would exacerbate cardiac symptoms (class 1a antiarrhythmic -
- Procainamide -> Also class 1a antiarrhythmic - see above
An adolescent girl presents with an acute theophylline OD 4 hours previously, which is least useful
- Haemodialysis
- α blocker
- metoclopramide
- verapamil
- potassium
α blocker.
Would worsen hypotension caused by B2 agonism
- Haemodialysis - definitive life-saving intervention
- metoclopramide - probably no particular role, but unlikely to cause harm
- verapamil - can cause SVT in OD, so betablockers can be used to treat this; presumably verapamil could be useful in this situation too
- potassium - treat hypokalamia associated with overdose
Hypotension in a theophylline OD is best reversed by
- Methoxamine
- Esmolol
- Dobutamine
- Dopamine
- Verapamil
Dobutamine
Beta-agonism
Flumazenil cannot reverse the action of
- Phenobarbital
- Meprobate
- Chloral hydrate
- Morphine
- All of the above
*
All of the above
- Only reverses benzodiazepines*
- Meprobamate = old tranquiliser*
- Chloral hydrate = very old halogenated sedative without any approved medical uses*
- Phenobarbital = barbituate*
Symptoms of withdrawal following sudden cessation of benzodiazepines usually last for
- 6-8 hours
- 24-48 hours
- 3-5 days
- 7-10 days
- 3-4 weeks
24-48 hours
cannabinoids
- produce tachycardias
- have an antipsychotic action
- act at a number of nonspecific receptors
- constricts the pupil
- all of the above
produce tachycardias
- Can worsen psychosis*
- Act at cannabinoid receptors*
- Dilate the pupil*
Wernicke’s encephalopathy is
- Coma, ophthalmoplegia and areflexia
- Confusion, ophthalmoplegia and ataxia
- Nystagmus, areflexia and ophthalmoplegia
- Nystagmus, hyperreflexia and ataxia
- A contraindication to IV dextrose
Confusion, ophthalmoplegia and ataxia
Definitely correct - confusion, ataxia, and ophthalmoplegia usually nystagmus are the classic triad
A contraindication to IV dextrose
At least a relative contraindication - giving dextrose without first giving thiamine can cause depletion of thiamine and precipitate Wernickes
Which of the following does not contribute to the pharmacologic effects of cocaine
- Inhibition of NA reuptake
- Inhibition of DA reuptake
- Inhibition of 5-HT reuptake
- Increased NA synthesis
- Increased 5-HT synthesis
Increased 5-HT synthesis
hyperactivity, chest pain and hypertension in a 30yo male is most likely due to
- marijuana intoxication
- alcohol intoxication
- Broncos failure to make the finals
- Cocaine intoxication
- Mushroom poisoning
Cocaine intoxication
The major rate limiting enzyme step in the metabolism of ethyl alcohol is
- Peroxisomal Catalase
- P-450 oxidases
- Acetaldehyde dehydrogenase
- NAD reductase
- Alcohol dehydrogenase
Alcohol dehydrogenase
Lack of acetalydehyde dehydrogenase can cause flushing symptoms and headache etc due to accumulation of acetaldehyde
