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Duration of Fentanyl and Metabolites in Urine and Saliva.


The purpose of this study was to look at the usefulness of fentanyl metabolites in the identification and tracking of drug usage. Urine and saliva samples from seven female patients who were given minor dosages of fentanyl were examined for the presence of fentanyl and its metabolites, norfentanyl and despropionylfentanyl. Samples were taken using gas chromatography/mass spectrometry up to 96 hours after the drug was administered. While norfentanyl was present in higher levels and identified up to 96 hours, unchanged fentanyl was evident in urine immediately postoperatively and in some patients after 24 hours. There was no despropionyl fentanyl found in the urine. Saliva regularly tested negative for fentanyl and its metabolites. The preferred drug for fentanyl abuse testing may be urine norfentanyl. This study emphasises the difficulties and possible use of metabolites in drug abuse.These findings suggest that urine norfentanyl may be a more reliable indicator of fentanyl abuse compared to unchanged fentanyl or despropionyl fentanyl. However, further research is needed to fully understand the metabolism and detection window of these substances in different individuals. 


Because of its euphoric effects, fentanyl, a powerful opioid painkiller, is being abused more and more. Fentanyl’s fast metabolism and elimination make it difficult to detect and track usage. The purpose of this study was to evaluate the usefulness of fentanyl metabolites in saliva and urine for monitoring and detecting drug misuse.The study aimed to assess the accuracy and reliability of fentanyl metabolite detection in both saliva and urine samples. Understanding the effectiveness of these biomarkers could potentially enhance drug misuse detection strategies and contribute to better monitoring of fentanyl abuse. This study involved collecting saliva and urine samples from individuals who were known to have misused fentanyl. The samples were then analysed to determine the presence and concentration of fentanyl metabolites. The results of this study could provide valuable insights into the potential use of saliva and urine testing as a means of detecting fentanyl misuse in real-world settings. 


The study included seven female patients who were given minor doses of fentanyl (110 +/- 56 mcg). Samples of saliva and urine were taken up to 96 hours after the medication was administered. Gas chromatography/mass spectrometry was used to extract fentanyl and its metabolites, norfentanyl and despropionylfentanyl, from samples and evaluate them.The results showed that fentanyl and its metabolites were detectable in both saliva and urine samples throughout the 96-hour monitoring period. The levels of norfentanyl and despropionyl fentanyl were found to be significantly lower compared to fentanyl, indicating rapid metabolism and elimination of these metabolites from the body. 


Urine from some patients showed unchanged fentanyl 24 hours after surgery, but by 72 hours it had disappeared. At 48 hours and in some patients at 96 hours, norfentanyl, which is present in higher concentrations than fentanyl, was found in all of the patients. There was not any despropionyl fentanyl found in any urine samples. Saliva samples did not consistently contain fentanyl or its metabolites. These findings suggest that fentanyl is rapidly eliminated from the body through urine within 72 hours after surgery. However, the presence of norfentanyl in urine samples at 48 and 96 hours indicates a slower elimination rate for this metabolite. Additionally, the absence of despropionyl fentanyl in all urine samples suggests that this particular metabolite may not be a significant contributor to fentanyl metabolism. Interestingly, the inconsistent presence of fentanyl and its metabolites in saliva samples highlights the need for alternative methods of drug detection in certain cases. 


According to the study’s findings, urine-based norfentanyl may be a more accurate indicator of fentanyl abuse than fentanyl that hasn’t changed. Norfentanyl in urine has a longer detection window than unmodified fentanyl, which makes it a good option for fentanyl use monitoring. Despropionylfentanyl, however, was not found in urine, suggesting that it has limited relevance as a marker for fentanyl usage. The study’s results highlight the importance of considering different metabolites of fentanyl when monitoring its abuse. While urine-based norfentanyl provides a longer detection window, the absence of despropionyl fentanyl in urine suggests that it may not be as useful in determining fentanyl usage. Further research is needed to explore other potential markers for accurate monitoring of fentanyl abuse. 


Based on this study, saliva testing does not seem to be a practical substitute for monitoring and detecting fentanyl usage, even though urinary norfentanyl shows potential as a marker. To confirm these results and investigate potential alternative biomarkers for the detection of fentanyl usage, more investigation is required. Developing efficient plans for substance addiction monitoring and intervention requires a better understanding of the metabolism and excretion kinetics of fentanyl.Additionally, future research should explore the correlation between fentanyl usage and other bodily fluids, such as blood or hair samples, to determine if they provide more accurate and reliable results. Understanding the pharmacokinetics of fentanyl will also aid in developing targeted interventions and treatment strategies for individuals struggling with fentanyl addiction.

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