Introduction Case 1 Case 2 Case 3 Case 4 Case 5 Case 6 References

The Patient Scenario
A patient is prescribed transdermal fentanyl therapy for chronic pain. In a follow-up visit, the patient has complained of activity-related pain which she would like treated. Specifically, she requests oxycodone to ease this episodic pain. The physician wonders if the patient is demonstrating drug-related aberrant behavior and obtains an onsite urine drug test that includes opiates in its drug panel profile.

The Test
Point of Collection/Care (POC) Immunoassay Testing for Opiates

The Test Results
The test is negative for opiates.

The physician struggles with interpretation of these results.
Do you think this patient is a diverter?


Synthetic opioids such as fentanyl and meperidine will not be detected by routine opiate immunoassays.

Next steps?


As clinical POC drug testing advances, specific immunoassay reagents are being developed that identify specific rather than general, classes of compounds. For example, methadone and oxycodone are both available as cost-effective, distinct POC immunoassay tests.

The strengths and limitations of these tests must always be borne in mind when interpreting results. Compliance testing (ie, looking for prescribed medications) should always be used in a patient-centered fashion and not as definitive evidence of adherence or non-adherence with the previously agreed upon treatment plan and not as definitive evidence of diversion.

The Physician’s Next Steps
A call to the reference lab for advice provides important information. The sample is retested at the lab specifically for nor-fentanyl using comprehensive testing, and results are positive for fentanyl.

Patient-Physician Discussion
After discussing the latest urine test results with the patient, the physician is reassured that the patient is in fact continuing to use her prescribed fentanyl patches. On further examination, the patient indicates that due to the loss of insurance coverage, she has been changing patches not every 3 days but rather every 4 or 5 days to save money. She explains to the doctor that she asked for the oxycodone because it is less expensive than the transdermal fentanyl patch and she thought she could combine use of each to ease her pain while saving money. Unfortunately, she is experiencing an increase in pain in response to her ‘economically driven solution.’

Transdermal fentanyl is a synthetic opiate of high potency (80-100 times more potent than morphine). It will never trigger a positive “opiate” screen. In fact, it requires a specific test to identify it or its metabolites presence in the urine.

The opiate immunoassay test is primarily sensitive to the naturally occurring alkaloids (codeine/morphine), unreliably sensitive to the semi-synthetics (oxycodone/hydrocodone/hydromorphone, etc) and reliably insensitive to the synthetic members of the opioid class of drugs (fentanyl/methadone etc).

If you are interested in any specific molecule, especially a high-potency opioid like fentanyl, the lab should be informed in advance of sample submission to insure that the results obtained are most likely to answer the intended question.

Seek guidance from the testing lab, if necessary, to confirm appropriateness of test selection.

The Patient-Physician Communication
With any unexpected laboratory result, communication with the patient and the lab may help to clarify the clinical significance of the result.  

It is critical to have an open and honest dialogue with the patient to determine the root cause of any apparent aberrant drug-related behavior.

The Final Outcome
The physician suggests and the patient agrees that rotation from transdermal fentanyl to a less expensive but effective analgesic agent is warranted.

Not all opioids will be detected when using a urine drug test that includes an opiate panel.
Aberrant drug-taking behavior is not always a definitive sign of drug abuse or misuse. When a problem arises, UDT results may assist in clarifying the clinical picture by providing objective data.

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Case 1:
Low back pain

Case 2:
High-risk patient

Case 4:
Escalating opioid doses

Case 5:
pain patient

Case 6:
Comorbid depression & anxiety