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Flashcards in toxins/pharmacology Deck (76):
1

What 4 toxins are not removed with charcoal?

CALM = cyanide, alcohol, lithium and heavy metals

2

A 3 y/o swallowed a battery 3 days ago. He is asymptomatic. What do you do?

Endoscopy. If in the esophagus or stomach it must be removed

3

When should swallowed coins be removed?

If proximal esophagus - endoscopy ASAP!
If middle to lower esophagus, observe 24 hours if asymptomatic and if does not pass then endoscopy needed

4

What are 3 initial manifestations of Tylenol toxicity?

Anorexia, nausea and vomiting

5

How long is the latent phase of acetaminophen toxicity?

1-4 days with significant rise of liver enzymes

6

What are the important 4hr post Tylenol ingestion levels to remember?

>150 = moderate toxicity
>300 = severe toxicity

7

Female ingested Tylenol 2 days ago. Acetaminophen level 4 hr post ingestion was 250 and she was treated with N acetylcysteine. Today LFTs are normal. What is her prognosis?

LFTs can be normal until 4 days after ingestion even after severe overdose! Pt is still in danger...

8

What is the initial management of acetaminophen ingestion ?

Charcoal then 4 hour post ingestion level

9

If >150mg/kg has been ingested, what should you do?

Immediately give N acetylcysteine, even before obtaining post ingestion levels

10

If a patient had wintergreen odor on breath, what should you be concerned about?

Aspirin ingestion

11

What is the initial treatment of salicylate ingestion?

Charcoal then 3-6hr post ingestion level

12

How do you manage ibuprofen ingestion ? What should you NOT do?

Do give supportive care and test for co-ingestion of aspirin or Tylenol
Do not give ipecac or gastric lavage,

13

What occurs physiologically after aspirin ingestion?

Respiratory alkalosis due to increased breathing --> buildup of organic acids and anion gap metabolic acidosis

14

What is the formula for anion gap?

Na - (Cl + bicarb)

15

What is the treatment for anion gap metabolic acidosis secondary to aspirin ingestion and why?

Sodium bicarb to alkalinize the urine

16

Which ingestion is associated with hypoglycemia ?

Ethyl alcohol

17

At what blood alcohol level can coma, respiratory depression and death occur?

>0.4

18

What products contain methanol?

Rubbing alcohol, Windshield washer fluid, cooking fuel, perfumes and antifreeze

19

Clinical presentation of methanol ingestion ...

Acidosis, increased anion gap and CNS depression

20

What is the antidote to methanol toxicity and why?

4-methypyrazole or ethanol --> alcohol dehydrogenase antagonist which slows conversion to formaldehyde

21

What are the classic symptoms of opiate toxicity?

Responsive to painful stimuli
Pinpoint but reactive pupils
Respiratory depression
Bradycardia, hypotension and low temperature

22

How can you differentiate opioid toxicity from dka?

Dka has rapid deep breathing with no miotic pupils
Opiates cause shallow breathing with miotic pupils

23

How can you differentiate opioid toxicity from organophosphate poisoning?

Both have pinpoint pupils but only organophosphate shave sweating, tearing and wheezing

24

What toxicity would be suspected in a person with dilated pupils and violent behavior?

Pcp

25

What is propoxyphene and what can it cause ?

Narcotic analgesic that can cause ventricular arrhythmia, seizures and pulmonary edema

26

What is the mechanism of action of organophosphates?

Acetylcholinesterase inhibitor

27

What are the classic signs of organophosphate poisoning?

DUMBBELS = diarrhea, urination, miosis, bronchospasm, bradycardia, emesis, lacrimation, salivation

28

What are the muscarinic effects of cholinergics and how are they treated?

Bronchospasm and increase pulmonary secretions - give atropine

29

What are the nicotinic effects of cholinergics and how are they treated?

Neuromuscular effects / treat with pralidoxime

30

What are the life threatening signs associated with TCA ingestion and when does this occur?

Dysthymia and hypertension occurs within 24 hours

31

What medications classically are known to have anticholinergic side effects?

Tricyclics, pupil dilator agents and antispasmodics

32

What are the anticholinergic signs?

Blind as a bat (dilated pupils)
Red as a beet
Hot as a hare
Dry as a bone
Mad as a hatter
Bowel and bladder lose their tone
Heart runs alone

33

How do you manage TCA ingestion?

Charcoal
alkalinization of urine
EKG monitoring for wide QRS

34

How do you treat a widening QRS after TCA poisoning?

Sodium bicarb boluses until QRS <100 msec

35

What are symptoms of beta blocker ingestion?

Depressed sensorium, bradycardia, hypotension and diaphoresis

36

What types of testing is invalid if a patient is taking TCAs and why?

TCAs render allergy testing unreliable because they interfere with histamine response

37

What occurs on labs and imaging after hydrocarbon ingestion?

Hypoxemia and ARDS (diffuse bilateral infiltrates on cxr)

38

How do you treat an asymptomatic patient after hydrocarbon ingestion?

Observation x 6 hours with pulse oximetry.

39

What ingestion should you consider in a patient with confusion and weakness but no fever?

Carbon monoxide

40

You are presented with a patient who is lethargic, confused and in distress. Vitals are normal. What is the best treatment?

100% oxygen

41

If suspected carbon monoxide poisoning but no improvement of symptoms despite 100% oxygen what should you consider?

Cyanide poisoning

42

What are 3 options for treatment of cyanide poisoning ?

Hydroxocobalamin
Sodium thiosulfate
Nitrate

43

When do you consider hyperbaric treatment after carbon monoxide toxicity?

Pregnancy, acidosis, cardiac involvement or neurological involvement

44

What might have been ingested in a patient that appears drunk with oxalate crystals on urinalysis?

Ethylene glycol

45

What is seen in the first phase of ethylene glycol toxicity?

Nausea, tachycardia, hypertension, metabolic acidosis and calcium oxalate crystals with hypocalcemia

46

What is the cause of coma or cardio respiratory failure during phase 2 of ethylene glycol toxicity?

Large anion gap acidosis and hypocalcemia

47

What occurs in phase 3 of ethylene glycol toxicity and how is it treated?

Acute tubular necrosis with renal failure requiring dialysis

48

At what level is iron ingestion considered toxic?

40 mg/kg of elemental iron

49

What lab findings are consistent with iron toxicity?

4hour post ingestion level > 350
WBC >15
Glucose> 150
Elevated LFTs
Metabolic acidosis

50

What are 4 major multisystem effects of iron ingestion?

Metabolic acidosis
Coagulopathy
Cardiovascular collapse
GI obstruction

51

What is the appropriate treatment for significant iron toxicity? What is not used for iron toxicity?

Defuroxamine chelation
Not charcoal as poor absorption

52

What are indications for iron chelation therapy?

Anion gap acidosis
Iron >500
Significant number of pills seen on KUB

53

When can deferoxamine treatment be stopped?

When clinical improvement and urine no longer pink

54

What are classic presenting signs on a patient following ingestion of caustic substance?

Coughing, drooling, difficulty swallowing and chest pain

55

What is the initial management for suspected caustic substance ingestion?

Endoscopy within 48 hours

56

What is recommended for treatment of alkali ingestion?

Observation 6 hours
Endoscopy if symptoms
No activated charcoal as will inhibit endoscopic exam

57

What are PCBs and what can they cause?

Synthetic hydrocarbons that cause Pigmentation/rash, Cutting teeth early and Birthweight that is low

58

How can you differentiate varicella vs smallpox lesions?

Smallpox - starts in face and extremities with lesions in same stage.
Chicken pox - starts centrally and spreads with lesions in varying stages.

59

What is a lesion that starts as an itchy papule that becomes bullous w central necrosis that is black and painless?

Cutaneous anthrax

60

What 5 medications are affected with use of St. John's wort and why?

OCPs
Iron
Digoxin
Anticoagulants
Antiretroviral drugs
*induction of P450 increases drug elimination

61

How is echinacea believed to act? When is it contraindicated?

Acts by modulating cellular immunity
Contraindicated in patients on immunosuppressants

62

What 5 drugs can interact with ginseng?

Anticoagulants
Anti platelets
Steroids
Hypoglycemic medications
Diuretics

63

When should valerian root not be used?

In patients using alcohol or other sedating drugs

64

Isotretinoin and griseofulvin should be taken with what types of foods?

Fatty foods (the drugs are lipophilic)

65

Which 3 medications should not be taken with dairy products ?

Tetracycline
Doxycycline
Ciprofloxacin

66

When is steady state of a drug achieved?

After 4-5 half lives

67

What 4 drugs cause inhibitory effects on hepatic enzymes and thus increased toxicity of many drugs?

Erythromycin
Ciprofloxacin
Cimetidine
Omeprazole

68

What 4 medications are considered potent enzymatic inducers which decrease the levels of many other medications ?

rifampin
Phenobarbital
Carbamazepine
Phenytoin

69

What 2 drugs decrease bioavailability of calcium, iron and magnesium?

Cephalosporins and fluoroquinolones

70

What two drugs inhibit renal metabolism of digoxin and lead to toxicity?

Quinidine and amiodarone

71

What is the appropriate medication to give for a patient with adrenal insufficiency who requires stress dosing?

IV hydrocortisone

72

What are 4 major side effects of beta blockers ?

Sexual dysfunction
Insomnia
Bronchospasm
Bradycardia

73

What type of drug is acetazolamide and how does it work?

Carbonic anhydrase inhibitor
Blocks teuptake of bicarb causing metabolic acidosis and alkaline urine

74

What are two major side effects of LASIX use?

Ototoxicity
Renal toxicity

75

What is the mechanism of action of loop diuretics and what electrolyte changes are seen?

Block absorption of Na and Cl
Wasting of Ca, K and H
Hypochloremic hypokalemic alkalosis

76

What is the appropriate dosing of activated charcoal?

0.5-1 g/kg (max 100g)