Why False Positives are Problematic for Opioid Testing

The opioid epidemic is continuing to grow. Estimates suggest as many as 2,000,000 Americans have a substance abuse disorder involving opiates, and the rate of fatal overdose has been steadily rising since 2000 with no signs of slowing down.

 

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Testing for Opioid Use

It’s no wonder so many businesses, governmental entities, and organizations are vested in more accurate testing for opioid use. The trouble with opioids is that they can be used both legally and illegally; for many, prescription painkillers act as a gateway to other, harder opioids like heroin. In 2015, nearly half of all opioid overdoses involved synthetic or semisynthetic drugs such as morphine, oxycodone, or fentanyl.

Opiates belong to a class of compounds noted for the way in which they interact with their endogenous opiate receptors. Synthetic opioids are notoriously difficult to detect and typically require separate immunoassays for screening.

 

False Positives in Opiate Testing

The primary toxicology tests used for opioid testing are antibody-based immunoassays and specific drug identification tests. The former is cost effective and typically quite sensitive, but its specificity is limited by cross-reactivity. False positives can result due to cross-reactivity through direct binding of the antibody, either from ingestion of a common opiate (such as poppy seeds) or even some common medications (such as quinolone antibiotics.)

It is particularly difficult to detect opioid abuse in patients who are already taking legally prescribed opiates. Prescription codeine, for example, can result in a false-positive for heroin use as both codeine and heroin share morphine as their metabolite. Likewise, patients being treated for the avoidance of opiates may be given buprenorphine; in some cases, actual heroin use has presented as a false-positive for buprenorphine, failing to alert medical professionals of continued illicit drug use.

 

Solving the Problem of False Positives

Urine analysis for the presence of specific opioids is a more complicated process than traditional urine drug testing. Most synthetic and semisynthetic opioids have their own EIAs; a full roster of EIAs should be on-hand in any laboratory or clinical setting. The concentration of urine can also prove problematic, particularly when the sample has been tampered with or diluted in any way.

IMCSzyme is advancing the science of drug testing through faster, more comprehensive hydrolysis. In less than 15 minutes, the enzyme can reach over 90% hydrolysis for a wide array of opiates including codeine-6, benzodiazepine, and morphine-3. By reducing the incubation period for the testing of commonly prescribed/abused opiates, IMCSzyme expedites the process of any follow up specificity testing that might ensue.


Are you interested in a better, more reliable solution for drugs of abuse testing in your lab or clinic? Find more information on IMCSzyme’s technical specifications here, or reach out to an IMCS team member today to talk further.