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Prescribed Fentanyl Patch For Long Term Pain Management. Drug Test Negative. Why Medication Not Showing In Urine Test?
I was prescribed the fentanyl patch 25 about 3 months ago after long term pain management. I was not prescribed anything for the breakthrough pain other than ibuprofen 600mg 3 x a day and I take Gralise 600mg three with my evening meal. I have had 2 drug tests and both have come back negative for fentanyl. I wear the patch as prescribed, I am on a 48 hour change rotation. Why would the medication not show up in my urine tests? I am using it, I would not be able to function if I wasn t; I have to work full time and I would not be able to get through the day without some relief. I have severe back pain, 3 herniated discs, and neuropathy. I had back neuro surgery about a year and a half ago to relieve compression on the sciatic. I don t understand why the fentanyl does not show up.
Mon, 18 Nov 2013
Hi there,
Thanks for your query.
Most of the drugs are detoxified and thrown out of the body through either kidneys or Liver. Fentanyl is detoxified by liver and excreted by it in the bile, which in turn, is thrown out of the body in the stools.
Hence, the urine tests negative for fentanyl. Only those drugs which are excreted from the body by the kidneys, are detected in urine.
If you find my response helpful and informative, do not forget an “excellent” rating to my answer, to encourage all doctors- engaged in social service- to render sound advice to the FREE queries.
Fond regards and have a nice day
Dr. Rakesh Karanwal
Thanks for your query.
Most of the drugs are detoxified and thrown out of the body through either kidneys or Liver. Fentanyl is detoxified by liver and excreted by it in the bile, which in turn, is thrown out of the body in the stools.
Hence, the urine tests negative for fentanyl. Only those drugs which are excreted from the body by the kidneys, are detected in urine.
If you find my response helpful and informative, do not forget an “excellent” rating to my answer, to encourage all doctors- engaged in social service- to render sound advice to the FREE queries.
Fond regards and have a nice day
Dr. Rakesh Karanwal
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