Intoxication, Drugs of Abuse Testing
TABLE 1: Medications/Substances Causing False Positives/Cross-Reactions (Preliminary Testing)
Pain relievers such as Advil, Nuprin, Motrin and menstrual cramp medications like Midol and Trendar. All drugs containing Ibuprofen. Passive marijuana smoking. It has been described that passive marijuana inhalation at a rock concert can test positive in the urine despite the fact that the person has not been using marijuana.
Dristan Nasal Spray, Neosynephren, Vicks Nasal Spray, Sudafed, and others containing ephedrine or pnenypropanolamine.
Vicks Formula 44M containing Dextromethorphan, and Primatene-M containing perylamine, as well as the pain reliever Demerol and prescription anti-depressant Elavil, and even Quinine Water
NyQuil Nighttime Cold Medicine
Antibiotics such as Ampicillin and Amoxicillin.
Diazepam, as well as some ingredients in cough medicines, Dextromethorphan.
Poppy seeds such as on a Burger King roll, bagel rolls (according to the Journal of Chemical Chemistry, Volume 33, #6, 1987), quantities of poppy seeds ingested in this study 25 and 40 grams, may be expected to be contained in 1 or 2 servings of poppy seed cake. Therefore, poppy seeds represent a potentially serious source of falsely positive results in testing opiate abuse. The paper in Clinical Chemistry also concludes: "Not only is it difficult to distinguish heroine or morphine abuse from codeine, but dietary poppy seeds can give a strong positive results for urinary opiates for several days duration that is confirmed by GC/MS analysis."
The list of agents which can cause false positivity in the urine has also been described for endogenous excretion of enzymes in the urine. For instance, a study from Emory University by Dr. James Woodford, has shown that a percentage of persons of African origin, orientals and Pacific Islanders may be testing positive for marijuana secondary to a mechanism which involves the pigment melanin which protects the skin from sun, which approximates the molecular structure of the THC metabolite which causes laboratory cross reaction with marijuana.
What this means is that if you have used any of these over-the-counter medications, you may be accused (arrested) based on a false positive urine test. If your expert does not pick this up you may be in serious irreversible trouble.
Methodology of Drug Screening in Urine
There are several methods to detect drugs in the urine. The most frequent one is an enzyme immunoassay (EIA), or radioimmunoassay (RIA), and florescence polarization immunoassay (FPIA). There are additional more sophisticated methodologies which are performed on extract of urine which are performed using thin layer chromatography (TLC), gas chromatography (GC) high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GS/MS). The only accepted procedures based on the definition of the National Institute of Drug Abuse (NIDA), and the Department of Defense (DOD), are immunoassays followed by gas chromatography/mass spectrometry confirmation. The confirmation utilizing gas chromatography/mass spectrometry is required since the methodology of immunoassay can give false positive results due to cross reactivity. This is due to the fact that this methodology cannot specifically identify the drug, but rather the antibodies recognize substances which may have the same structure chemically, or immunologically or enzymologically, other than the drug of interest. Immunoassays for amphetamines will show reactivity with drugs structurally related to amphetamines, such over-the-counter sympatomedicoamines, phenylpropanolamine and ephedrine, over-the-counter legal medications used for nasal congestion, cold and appetite suppressant. Confirmation therefore is a must utilizing gas chromatography/mass spectrometry. The use of gas chromatography/mass spectrometry provides an extremely high index of reliability when properly preformed and applied.
As far as gas chromatography/mass spectrometry, this is a superb methodology if done correctly. For instance, if the equipment has not been cleaned appropriately, the previous run from the previous testing will contaminate the next sample, and will give erroneous, inaccurate and incorrect results. Therefore, it is mandatory to look into the methodology that the person used for specific results on gas chromatography/mass spectrometry at a given indicated case. (On many occasions a deposition of the lab technician will reveal that the sample was contaminated.)
What this means to you is that if your urine is tested utilizing the immunological method only, without confirmation with GS/MS, there is a high probability that the result may be a false positive and irrelevant to your situation.
Forensic Accuracy of GS/MS
Gas chromatography/mass spectrometry is extremely and highly accurate if done correctly. A laboratory which performs the test must be NIDA certified or CAP (College of American Pathologists) certified. All of the labs that perform the gas chromatography/mass spectrometry on site can be NIDA certified. Labs that send samples to another laboratory for gas chromatography/mass spectrometry confirmation are ineligible, I repeat, ineligible, for NIDA certification. Therefore one must be very careful when looking at the test results to see whether the laboratory is NIDA/CAP certified. Furthermore, some labs do not properly and thoroughly clean the GC/MS equipment. Some labs don't even do GC/MS confirmation. Some labs use cheap alternative methods to increase profits and reduce expenses. Therefore you must be in a position to aggressively cross examine the laboratory director and technician.
Drug of Abuse and Hair Testing
Hair testing for drug of abuse testing has become extremely popular among employers. There have been several scientific forensic doubts about the use of this methodology for proof of abuse. For example, the Society of Forensic Toxicologists in 1990 stated: "The use of hair analysis for employees in pre-employment drug testing is premature, and cannot be supported by the current information on hair analysis for drugs of abuse." A 1997 study by the National Institute of Drug abuse reached a conclusion and indicated that significant ethnic bias may be the result of test for cocaine positivity. Analytical Toxicology in its issue in March/April 1998 indicated that removal of melanin from hair (a methodology used to remove the ethnic bias) "does not eliminate the hair color bias when interpreting cocaine concentrations" Public information available (Congressional records from May 14, 1999), indicated that the Department of the Army secretary raised questions about the Army's use of hair testing in a specific case, and members of Congress were expressing their discomfort with the procedure's reliability. Indeed, Representative, Cynthia McKinney, a Democrat of Georgia, and from Defense Secretary, William Cohen, that she is exploring possible Legislative remedy to prohibit human hair testing for drugs in the military, given that the hair testing has been proven by forensic toxicologists to be racially biased. Indeed, the paper by Kintz, et. al. published in the Journal of Forensic Scientific International, January 1997, Volume 17, pages 84 to 123 and 151 to 156, indicated that false positives are found even at low concentrations. Tissue hair analysis in good hands with good laboratory technology may give an idea about habitual use of some of the drugs; however, it is preferable that these should be combined with urinalysis utilizing either screening, or better confirmation methodology.
Practical Application to a Case Analysis
In order to summarize and make the above data applicable, I will describe two case scenarios.
A 28-year-old worker fell off the roof, 2nd floor, while on the job. He suffered several bone fractures, head contusion and was taken to the emergency room. At the emergency room urine was sent to the lab for drug screening. Upon recovery from the injury the patient requested Workers Compensation benefits, and was denied since the urine drug screening utilizing EMIT methodology (immunological) detected opiates. In his deposition the patient testified that he has never used drugs, did not use drugs on the date of injury either. On careful review of the medical records, it turned out that the physician on behalf of the employer had recommended denial of the Workers Compensation benefits, failed to review the paramedic ambulance notes which was called to the scene of the injury and had transferred the patient to the hospital. The emergency room notes sheet indicated that the patient had received IV morphine from the medic driver to sedate him from his severe pain of bone fractures and skull concussion. The evaluating physician further failed to note that the urine sample was obtained 4 hours after the patient's stay in the emergency room, and did not specify whether that was a fresh urine sample, catheterized urine, and did not specify the volume of the urine. The patient's physician provided a report documenting that there is no history of drug abuse, there was no evidence that the patient was impaired from testimonies from his supervisors and coworkers on the date that the injury occurred, and has further provided evidence that the urinalysis was taken several hours after the patient was administered IV morphine by paramedics at the emergency room, and therefore, the results were essentially erroneous and irrelevant to the patient's cause of injury. This is an example of how drug urine testing can be applied wrongfully, and cause unnecessary pain, anxiety, delay of benefits and major expenses to the insurance carrier and the citizens who end up paying these expenses out of their pocket.
This is a 32-year-old female patient, a driver of a vehicle who was involved in a car collision and suffered internal bleeding (ruptured spleen), and a fracture of a bone of the lower extremity. She had requested medical benefits from her insurance carrier for medical expenses as well as time lost from work, and has filed a lawsuit since these were denied. The physician who examined the patient on behalf of the insurance carrier, and whose report was the basis for the denial, noted in his reports that upon admission to the emergency room on the date of injury, urine screening test for toxicology was done, and was positive for amphetamines. The physician who examined the patient on behalf of the insurance carrier failed to note the time of the testing, the time the urine was obtained from the patient, whether the patient was taking any medications which contain amphetamines, such as ephedrines or pseudoephedrines. The medical records examined carefully by the patient's physician, found notes from the house doctor who attended the patient at midnight on her admission. The house doctor took a good detailed history recorded in his handwriting which clearly stated that the patient is an allergic individual, and has for the last two weeks been using compounds which contain both ephedrine and pseudoephedrine. The physician who reported on behalf of the patient further was able to show in the medical records that all examining physicians clearly stated that the patient was alert x 4 on admission to the hospital, despite her pain and despite medications received from the paramedics and emergency room physicians. There was no clinical evidence of impairment, there was no history of drug abuse, there was no evidence of drug impairment. The problem with this case, is that the urine screening test was a false positive, because of the patient's use of over-the-counter ephedrine and pseudoephedrine containing medications to treat a cold and nasal congestion. Had a follow-up been done on that sample with gas chromatography/mass spectrometry showing a specific type of amphetamine, the story might have been different if indeed the patient was a user (which is not the case here). This case further illustrate: 1. The need for a very in depth evaluation of the chart and notes, as far as to the patient's mental capacity before and after the collision. 2. A detailed analysis of past and present prescription and over-the-counter medications. 3. The need to follow-up on urine screening test if it is positive for drugs of abuse in a case where such suspicion is indicated. Gas chromatography/mass spectrometry is the ultimate tool to eventually follow-up on such a suspicion.
In summary, while drug abuse and intoxication is a problem, the diagnosis of Aintoxicated@ is a scientific one and cannot be based on Apersonal beliefs@ or Afeelings@ of a defense examiner.
About Dr. Brautbar
Dr. Brautbar is board-certified in internal medicine, forensic medicine, and nephrology, with a specialization in toxicology. Dr. Brautbar has provided expert medical opinion and scientific evidence in product liability, personal injury, medical standards, and toxic tort cases throughout the United States. Dr. Brautbar is a Clinical Professor of Medicine at USC School of Medicine, Department of Medicine, and served as Chairman and Vice-Chairman of the Department of Medicine at the Queen of Angels/Hollywood Presbyterian Medical Center. He has published over 240 journal manuscripts, abstracts, and book chapters in the fields of internal medicine, toxicology, and nephrology. His resume includes past and present membership in 25 National and International Scientific Societies including the Collegium Ramazzini. Dr. Brautbar has been on the faculty of the National Judicial College and lectured to Judges on the issue of Scientific Evidence, and was a peer reviewer for the Federal Judicial Center (Reference Manual on Scientific Evidence, Second Edition, 2000). Dr. Brautbar has also been a peer-reviewer for the ATSDR.
Dr. Brautbar is a board-certified internist and nephrologist, and certified in forensic medicine. If you are interested in retaining Dr. Brautbar for forensic and expert witness testimony services, please submit the Contact Form.
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© 2013 Nachman Brautbar M.D.
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