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Millennium Laboratories Research Study Reveals Lower Opiate Cutoff Levels Identify Higher Percentage of Patients Taking Illegal Drugs

Findings to Be Presented in Poster Session at the 2009 AACC Annual Meeting on July 23rd

SAN DIEGO--(BUSINESS WIRE)--Jul 22, 2009 - Millennium Laboratories, represented by its Laboratory Director, Amadeo J. Pesce, Ph.D., DABCC, will present a poster titled, “False Negative Immunoassay Screening Results in Pain Patients,” at the 2009 American Association for Clinical Chemistry (AACC) Annual Meeting, July 19 through July 23, at McCormick Place Convention Center in Chicago. The poster session will be presented on Thursday, July 23, 9:30 am – 12 noon.

A world renowned toxicologist, Dr. Pesce is the author of thirty-two textbooks and more than two hundred peer-reviewed articles, CDs and workbooks on chemistry, toxicology, and drug testing procedures. The “False Negative Immunoassay Screening Results in Pain Patients” poster presentation at this year's AACC meeting concerns a research study conducted by Dr. Pesce and the Millennium scientific team of urine samples from 4,200 pain patients who were tested by immunoassay and LC/MS/MS for several drug classes, drugs, and metabolites. False negative results as determined by mass spectrometry were common. The greatest failures were for the benzodiazepine class (28%). Using a lower cutoff with LC/MS/MS the investigators observed double the number of cocaine-positive urines.

Dr. Pesce said, “The implications for clinical practice are that the national standards for cutoff levels need to be reexamined based on newer data available on drug abuse and lower cutoff levels. The quantitative drug analysis in pain patients is different from forensic drug testing because both positive and negative results have clinical interpretation as opposed to only positive results having significance. Negative results for patients on prescribed medication imply non-compliance or diversion. The usual practice for drug testing is to do an immunoassay screen followed by confirmation by mass spectrometry. Physicians are often unaware that common immunoassays do not detect many drugs of interest in pain management, which means negative results will be reported even though the patient is taking the drug.”

The Millennium Laboratories results support other documentation that in chronic pain patients false negative results are common when immunoassay screening methods are used and reiterate that the drug class descriptors used for many immunoassays are inaccurate. The research study found that 28% of immunoassay tests for benzodiazepines came up negative when the patient was found to be positive when tested by LC/MS/MS.

Another significant aspect of the Millennium Laboratories research is that it demonstrates with modern LC/MS/MS technology it is possible to lower the cutoffs for detection and confirmation of illicit drugs such as cocaine. When the cutoffs for cocaine were lowered the number of illicit drug users doubled in the population of chronic pain sufferers tested.

Dr. Pesce explained, “Our lower levels of detection can identify a higher percentage of patients taking illicit drugs, possibly endangering a physician's practice. Also, it prevents dismissing patients who may indeed be following their prescribed medication regimen.”

About AACC

AACC (American Association for Clinical Chemistry) is an international scientific/medical society of clinical laboratory professionals, physicians, research scientists and other individuals involved with clinical chemistry and other clinical laboratory science-related disciplines. More information on AACC is available at

About Millennium Laboratories

Founded in 2007 in America's biotech capitol, San Diego, Millennium Laboratories is rapidly becoming the Urine Drug Testing (UDT) resource of choice for physicians and staff focused on the treatment of chronic pain. Millennium Laboratories provides the fastest turn-around time in the industry for drug test reporting and confirmation of results because the company is the only major Urine Testing Laboratory exclusively utilizing the latest cutting-edge technology Liquid Chromatography/Mass Spectrometry/Mass Spectrometry (LC/MS/MS). The company is the only major Urine Drug Testing Laboratory licensed as a training facility for Toxicologist Scientists. Millennium Laboratories is in a dynamic growth mode, continuing to post double-digit growth quarter over quarter.

Certified, state-of-the-art advanced training at Millennium's 40,000 sq/ft. campus is an integral component of the University of California, San Diego's (UCSD) doctoral program in Pharmacy. Led by Laboratory Director Amadeo Pesce, Ph.D., world-renowned Toxicologist and author, the Millennium Laboratories team are experts in mass spectrometry and high throughput chemistry. The company has developed proprietary methodologies that provide the fastest reliable urine drug testing (UDT) confirmations in the nation, usually within one business day. For more information, visit the Millennium Laboratories website,


Contact: Millennium Laboratories
Renee Bryan, Vice President of Marketing, 877-451-3534
Media Contact:
Nsight Public Relations
Sandra G. Oak, 321-591-1508


Posted: July 2009