Opiates

Some prescription opioids overlap directly with opiate evidence. Morphine and codeine, for example, are naturally occurring opiates and may be prescribed medically. Other prescription opioids, including oxycodone and hydrocodone, fall within the broader opioid category rather than the narrower definition of opiates. CDC identifies morphine alongside hydrocodone and oxycodone as examples of prescription opioids. When prescription opioids are part of the case, the specific drug and disputed scientific question should guide the scope of analysis. Prescription history, dose, timing, administration records, metabolites, and laboratory findings may all affect how the evidence is interpreted.

The analysis may involve specimen type, collection and handling, screening procedures, confirmatory testing, reported analytes, cutoff concentrations, metabolites, quality-control documentation, and chain of custody. The HHS Mandatory Guidelines for Federal Workplace Drug Testing Programs identify specified opioid analytes and cutoff concentrations and provide requirements for initial and confirmatory testing of covered federal agency specimens. These details can matter when determining whether a laboratory finding reliably identifies the substance at issue and what conclusions can reasonably be drawn from that result.

A laboratory-confirmed positive result indicates that the tested substance or metabolite was identified in the specimen under the applicable analytical criteria, such as a specified confirmatory cutoff. In federal workplace-testing programs, a laboratory-confirmed positive result is subject to Medical Review Officer review and verification. A positive analytical result does not by itself establish impairment, overdose, causation, or the effect of the drug at a particular time. Those conclusions may depend on specimen type, concentration, timing, metabolism, tolerance, other substances, medical history, and the circumstances of the event. When those physiological or causal questions become central, Toxicology or other clinical expertise may be needed. NIJ describes forensic toxicology as the analysis and interpretation of drugs in biological samples, including consideration of concentrations and their potential relationship to illness, death, or impairment.