DRE Toxicology & Drug Testing Flashcards

Which type of drug interaction occurs when two substances together produce a greater-than-additive effect?

Answer: Synergism

Synergism (or potentiation) occurs when two drugs combine to produce an effect greater than the sum of their individual effects, increasing impairment risk.

A urine immunoassay screening test that returns a positive result must then undergo which step before being admissible in court?

Answer: GC-MS confirmatory testing

Positive immunoassay screens must be confirmed with GC-MS to provide the specificity and precision required for court proceedings.

Hallucinogens such as LSD primarily affect which neurotransmitter system, which DREs should understand when correlating findings?

Answer: Serotonin

LSD and other classic hallucinogens exert their effects primarily through agonism at serotonin (5-HT2A) receptors, producing perceptual distortions.

What is the half-life concept important for in a DRE toxicology context?

Answer: Estimating when a drug's concentration decreases by 50%

Half-life describes the time required for the plasma concentration of a drug to decrease by half, helping DREs understand the duration of likely impairment.

Dissociative anesthetics like PCP can produce which unique toxicological finding relevant to a DRE evaluation?

Answer: Horizontal gaze nystagmus without alcohol

PCP and other dissociative drugs can produce horizontal gaze nystagmus (HGN) independent of alcohol ingestion, which must be distinguished during evaluation.

Which term describes the time from drug ingestion to when peak blood concentration is reached?

Answer: Time to peak (Tmax)

Tmax (time to maximum concentration) indicates when the drug is at its highest level in the blood, which often correlates with peak impairment.