The abbreviation OPI on a drug test report stands for Opiates, representing a specific class of compounds within the larger category of opioids. This designation is commonly used in initial screening tests for employment or medical monitoring. A positive OPI result indicates that certain natural or semi-synthetic compounds derived from the opium poppy were detected above a predetermined cutoff level. Understanding this result requires differentiating between the various types of opioid substances and the testing methods used to identify them.
Decoding the OPI Designation and the Opioid Class
The term Opiate, or OPI, refers narrowly to substances naturally derived from the opium poppy, primarily morphine and codeine. These natural compounds are sometimes chemically modified to create semi-synthetic opiates, such as heroin. OPI testing focuses on detecting these natural and semi-synthetic substances and their primary metabolites, or breakdown products.
The broader term, Opioid, includes all substances that act on opioid receptors in the brain, encompassing natural opiates and fully synthetic compounds. Standard OPI panels usually target naturally occurring opiates, meaning they may not detect newer synthetic opioids like fentanyl, tramadol, or oxycodone. Detecting these synthetic substances requires the test panel to be specifically expanded, often including separate screening markers.
The compounds screened for under the OPI designation are morphine and codeine, the main natural alkaloids of the poppy. Heroin is rapidly metabolized, first into 6-monoacetylmorphine (6-MAM) and then into morphine. Because 6-MAM is unique to heroin use, its presence provides definitive proof of consumption, but it requires a specialized test and is only detectable for a short period. The presence of morphine alone can result from the use of heroin, morphine, or codeine since they all share morphine as a common metabolite.
How Opiates Are Screened and Confirmed
Drug testing for opiates follows a standard two-step process to maximize efficiency and accuracy. The first step is the initial screening, a rapid, cost-effective immunoassay test. This test uses antibodies designed to bind to opiate molecules, providing a result based on whether the drug concentration exceeds a specific cutoff level.
For opiates, the common federal cutoff level for this initial screen in urine is 2,000 nanograms per milliliter (ng/mL). This relatively high threshold was established to reduce the chance of false positive results from common exposures, such as consuming poppy seeds. If the concentration of opiates in the sample is below this cutoff, the sample is reported as negative and no further testing is typically done.
If the initial screen yields a presumptive positive result, the second step is confirmation testing. This confirmation uses highly precise laboratory techniques, most commonly Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Mass Spectrometry (LC/MS). These methods separate molecules in the sample and identify their unique chemical signatures, providing definitive identification of specific drug metabolites. Confirmation testing quantifies the exact concentration of substances like morphine and codeine, virtually eliminating the possibility of a false positive result caused by cross-reactivity.
Sources of a Positive Result: Prescription, Illicit, and Accidental Exposure
A positive OPI result can stem from multiple sources, including legitimate medical use, illicit consumption, or accidental exposure. The most straightforward explanation is the use of prescription medication containing morphine or codeine, such as pain relievers or cough suppressants. When these medications are legally prescribed, the presence of the opiate metabolites is expected and verified with proper documentation.
Illicit use of opiates is another source, particularly heroin, which breaks down into the detectable metabolites 6-MAM and morphine. While the presence of morphine alone is not sufficient to prove heroin use, the detection of the unique breakdown product 6-MAM is definitive evidence of recent heroin consumption. The relative concentrations of morphine and codeine can also sometimes help toxicologists determine the likely source.
A surprising source of a positive OPI result is the consumption of foods containing poppy seeds. Poppy seeds are harvested from the opium poppy plant and can become contaminated with latex containing morphine and codeine. Although the 2,000 ng/mL federal cutoff level significantly reduced the likelihood of a positive result from casual consumption, it remains possible. A high volume of contaminated poppy seeds can sometimes push urinary concentrations of morphine and codeine into the positive range.
The Verification Process Following a Positive OPI Result
After a laboratory confirms a positive OPI result using precise confirmation testing, the result moves to the verification stage. This stage involves a Medical Review Officer (MRO), a licensed physician specializing in drug testing and toxicology. The MRO’s role is to determine if there is a legitimate medical explanation for the confirmed positive result before reporting it to the employer or requesting entity.
The MRO contacts the individual for a confidential interview and requests documentation, such as a valid prescription, pharmacy records, or contact information for the prescribing physician. If the individual provides adequate documentation proving the opiate use was medically authorized, the MRO reports the result as “negative” or “verified” to the requesting party. This process ensures that individuals using legally prescribed medication are not unfairly penalized.
If the individual cannot provide a valid medical explanation for the confirmed presence of opiates, the MRO reports the result as a confirmed positive. The process is designed to be fair and medically sound, distinguishing between therapeutic use, accidental exposure, and unauthorized use. The MRO acts as a safeguard, interpreting laboratory data in the context of the individual’s medical history.