DOT Rule 49 CFR Part 40 Section 40.139
Subpart G - Medical Review Officers and the Verification Process
§ 40.139 On what basis does the MRO verify test results involving opiates?
As the MRO, you must proceed as follows when you receive a laboratory confirmed positive opiate result:
(a) If the laboratory confirms the presence of 6-acetylmorphine (6-AM) in the specimen, you must verify the test result positive.
(b) In the absence of 6-AM, if the laboratory confirms the presence of either morphine or codeine at 15,000 ng/mL or above, you must verify the test result positive unless the employee presents a legitimate medical explanation for the presence of the drug or drug metabolite in his or her system, as in the case of other drugs (see § 40.137). Consumption of food products (e.g., poppy seeds) must not be considered a legitimate medical explanation for the employee having morphine or codeine at these concentrations.
(c) For all other codeine and morphine positive results, you must verify a confirmed positive test result only if you determine that there is clinical evidence, in addition to the urine test, of unauthorized use of any opium, opiate, or opium derivative (i.e., morphine, codeine, or heroin).
(1) As an MRO, it is your responsibility to use your best professional and ethical judgement and discretion to determine whether there is clinical evidence of unauthorized use of opiates. Examples of information that you may consider in making this judgement include, but are not limited to, the following:
(i) Recent needle tracks;
(ii) Behavioral and psychological signs of acute opiate intoxication or withdrawal;
(iii) Clinical history of unauthorized use recent enough to have produced the laboratory test result;
(iv) Use of a medication from a foreign country. See § 40.137(e) for guidance on how to make this determination.
(2) In order to establish the clinical evidence referenced in paragraphs (c)(1)(i) and (ii) of this section, personal observation of the employee is essential.
(i) Therefore, you, as the MRO, must conduct, or cause another physician to conduct, a face-to-face examination of the employee.
(ii) No face-to-face examination is needed in establishing the clinical evidence referenced in paragraph (c)(1)(iii) or (iv) of this section.
(3) To be the basis of a verified positive result for codeine or morphine, the clinical evidence you find must concern a drug that the laboratory found in the specimen. (For example, if the test confirmed the presence of codeine, and the employee admits to unauthorized use of hydrocodone, you must not verify the test positive for codeine. The admission must be for the substance that was found through the actual drug test.)
(4) As the MRO, you have the burden of establishing that there is clinical evidence of unauthorized use of opiates referenced in this paragraph (c). If you cannot make this determination (e.g., there is not sufficient clinical evidence or history), you must verify the test as negative. The employee does not need to show you that a legitimate medical explanation exists if no clinical evidence is established.
[65 FR 79526, Dec. 19, 2000, as amended at 75 FR 49862, August 16, 2010; 77 FR 26473, May 4, 2012; 82 FR 52245, November 13, 2017]