CFPN Toxicology and Pharmacology in Forensic Cases 2 — Questions and Answers
Question 1: A patient presents with miosis, respiratory depression, and altered mental status. Which drug class is most likely responsible?
- Opioids (Correct answer)
- Stimulants
- Benzodiazepines
- Cannabis
Correct answer: Opioids
The classic opioid toxidrome includes miosis (pinpoint pupils), respiratory depression, and CNS depression.
Question 2: In postmortem forensic toxicology, which phenomenon can cause measured drug concentrations to differ from ante-mortem levels?
- Postmortem redistribution (Correct answer)
- Livor mortis
- Rigor mortis
- Decomposition gases
Correct answer: Postmortem redistribution
Postmortem redistribution occurs as drugs migrate from tissue reservoirs into blood after death, altering concentration measurements.
Question 3: Which medication is a common antidote used in forensic/emergency settings to reverse opioid toxicity?
- Naloxone (Correct answer)
- Flumazenil
- N-acetylcysteine
- Physostigmine
Correct answer: Naloxone
Naloxone is a competitive opioid receptor antagonist that rapidly reverses opioid-induced respiratory depression.
Question 4: What does a creatinine level below 2 mg/dL in a urine specimen indicate in forensic drug testing?
- Specimen is not consistent with normal human urine (substituted) (Correct answer)
- Normal dilute specimen
- High drug concentration expected
- Specimen was properly collected
Correct answer: Specimen is not consistent with normal human urine (substituted)
Creatinine below 2 mg/dL indicates the specimen is not consistent with normal or dilute human urine and is considered substituted.
Question 5: Which class of drugs is detected using the EMIT immunoassay for THC metabolites in urine, and what is the standard federal cutoff concentration?
- Cannabinoids at 50 ng/mL (Correct answer)
- Cannabinoids at 20 ng/mL
- Cannabinoids at 100 ng/mL
- Cannabinoids at 10 ng/mL
Correct answer: Cannabinoids at 50 ng/mL
The federal workplace drug testing cutoff for cannabinoid metabolites (THC-COOH) in urine immunoassay is 50 ng/mL.
Question 6: Ethanol's primary route of metabolism involves which enzyme system?
- Alcohol dehydrogenase (ADH) (Correct answer)
- Cytochrome P450 3A4 exclusively
- Monoamine oxidase (MAO)
- Glucuronyl transferase
Correct answer: Alcohol dehydrogenase (ADH)
Alcohol dehydrogenase in the liver is the primary enzyme that metabolizes ethanol to acetaldehyde.
CFPN Toxicology and Pharmacology in Forensic Cases 2
A patient presents with miosis, respiratory depression, and altered mental status.
Which drug class is most likely responsible?