Toxicology, Environmental & Infectious Diseases Flashcards

A patient presents with bradycardia, hypotension, and hyperkalemia after ingesting a large quantity of sustained-release verapamil. Which antidote provides the most direct physiologic benefit?

Answer: High-dose insulin with dextrose

High-dose insulin euglycemic therapy (HIET) improves myocardial carbohydrate metabolism and is the mainstay treatment for severe calcium channel blocker overdose.

A hiker returns from the Appalachian Trail with fever, headache, and a petechial rash spreading centripetally from the wrists and ankles. What is the treatment of choice?

Answer: Doxycycline

Doxycycline is the drug of choice for Rocky Mountain Spotted Fever (Rickettsia rickettsii) in all age groups, including children.

Which of the following is the MOST reliable antidote for methanol poisoning in the emergency setting when fomepizole is unavailable?

Answer: Ethanol IV infusion

Ethanol competitively inhibits alcohol dehydrogenase and prevents conversion of methanol to its toxic metabolite formic acid when fomepizole is unavailable.

A 22-year-old is brought in with hyperthermia of 41.2°C, muscle rigidity, diaphoresis, and clonus after starting linezolid while taking sertraline. Which intervention is MOST important to reduce mortality?

Answer: Lorazepam 2 mg IV and active cooling

Serotonin syndrome treatment prioritizes benzodiazepines for neuromuscular agitation plus aggressive cooling; cyproheptadine is adjunctive but oral delivery is slower.

A patient presents with respiratory failure, miosis, bradycardia, and excessive secretions after a farmworker exposure. What is the appropriate initial dose of atropine?

Answer: 2–4 mg IV, repeat every 5–10 min until secretions dry

Organophosphate poisoning requires aggressive atropinization starting at 2–4 mg IV titrated to drying of secretions, which is the clinical endpoint.

Which of the following correctly characterizes the Rumack-Matthew nomogram used in acetaminophen toxicity?

Answer: It predicts hepatotoxicity risk based on serum level plotted against time post-ingestion

The Rumack-Matthew nomogram plots serum acetaminophen concentration against hours post-acute ingestion to predict risk of hepatotoxicity and guide NAC treatment.

A patient presents with fever, neck stiffness, and photophobia. CSF shows glucose 30 mg/dL, protein 180 mg/dL, and 800 WBC/µL (90% neutrophils). Which empiric antibiotic regimen is most appropriate for an immunocompetent adult?

Answer: Vancomycin + ceftriaxone + dexamethasone

Bacterial meningitis in an immunocompetent adult is treated with vancomycin plus a third-generation cephalosporin; dexamethasone reduces inflammation and improves outcomes, particularly in S. pneumoniae meningitis.