Toxic/Drug abuse

Question 1

How does paraquat poisoning present?

Answer 1

Paraquat is a commonly used herbicide that tends to concentrate in the lungs and cause acute respiratory distress syndrome (ARDS). It is commonly used as a suicide agent in third world countries; in fact, most cases of paraquat toxicity are self-inflicted.

Question 2

What medication treats iron overdose?

Answer 2

Deferoxamine

Question 3

What medication treats clonidine overdose?

Answer 3

Naloxone or atropine

Question 4

What is treatment for lead poisoning?

Answer 4

Patients with symptomatic lead poisoning or extremely high lead levels in the blood (> 70 μg/dL) should be treated with both dimercaprol and calcium EDTA. With milder poisoning, intravenous or intramuscular
calcium EDTA or, more likely, oral dimercaptosuccinic acid can be used.

Question 5

How should salicylate poisoning be treated?

Answer 5

Excretion of salicylates in the urine can be markedly enhanced by the administration of acetazolamide and IV sodium bicarbonate. Hemodialysis can also be used.

Question 6

What birth defects can maternal use of isoretinoin (retinoic acid) cause?

Answer 6

Bilateral microtia or anotia (underdeveloped or absent ears), conotruncal heart defects, small or missing thymus, hydrocephalus, CNS abnormalities, micrognathia, and even fetal death.

Question 7

What treatment/interventions should be done in a child who drinks drain cleaner?

Answer 7

Drain cleaner is a strong base which can be caustic to the mucosa so endoscopic examination to assess the damage in the first 24-48 hours is recommended. Steroids may be helpful. Do not give agents to promote vomiting as this exposes the esophageal mucosa twice to caustic substances.

Question 8

What ingested substances does activated charcoal work best for?

Answer 8

For drugs with an enterohepatic circulation (eg, phenobarbital and tricyclic antidepressants), or those with prolonged absorption (eg, sustained-release theophylline), the use of multiple-dose activated charcoal can be effective in decreasing the half-life and increasing the total body clearance of the toxic substance.

Question 9

What ingested substances does activated charcoal not absorb well?

Answer 9

Alcohols, acids, ferrous sulfate, strong bases (such as drain cleaners and oven cleaners), cyanide, lithium, and potassium.

Question 10

How is aspirin overdose managed?

Answer 10

Alkalization of the urine

Question 11

How can ingestion of topical anesthetics (e.g. benzocaine/lidocaine) affect oxygenation status?

Answer 11

Acts as an oxidizing agent which can cause methemoglobinemia. Patients will have low pulse ox saturation but a normal PaO2 (unbound oxygen is normal). Treatment is with methylene blue.
Nitrites and dapsone can also cause methemoglobinemia.

Question 12

What acid-base disturbance can iron poisoning cause?

Answer 12

Anion-gap metabolic acidosis (due to cellular dysfunction and build up of lactate)

Question 13

What are the symptoms of iron overdose?

Answer 13

Abdominal pain, melena, hematemesis, hypotensive shock, metabolic acidosis eventually leading to hepatic necrosis and pyloric stenosis

Question 14

Above what level of a screening capillary lead level should a confirmatory venous lead measurement be drawn?

Answer 14

≥5 ug/dL (capillary/fingerstick specimens often have false-positive results)

Question 15

What is considered a mild lead level and how is it treated?

Answer 15

5-44 ug/dL. No treatment, repeat level within a month

Question 16

What is considered a moderate lead level and how is it treated?

Answer 16

45-69 ug/dL, treated with meso-2,3-Dimercaptosuccinic acid (DMSA)

Question 17

What is considered a severe lead level and how is it treated?

Answer 17

≥70 ug/dL, treated with dimercaprol plus calcium disodium edetate (EDTA)