false positive for hydrocodone

[onenanny]

After failed back surgery, I was referred to PM. This was about 1 1/2 years ago, neuro stimulator placed doing well with pain control using ibuprofen and Tylenol #4.  However according to PM Dr. last 3 dit have shown increased amounts of hydrocodone. I take ibuprofen, Tylenol #4, Prozac, diazyde, devastating, multivitamin, exception, and a topical compound which is formulated under Dr. order. I do not take hydrocodone. I am allergic to hydrocodone. I am at my wits end, what would cause this false positive.

[philnoir]

The metabolism of codeine results in other opioid metabolites, including morphine, and a minor amount of hydrocodone. In fact, this is how codeine works -- by itself, codeine is ineffective. But because it is metabolized into a small amount of morphine, it is effective against pain.

Depending on the laboratory method used by your doctor's testing service, false positives can be reported if their "cut-off level" is set too low.

The cut-off is the concentration at which a target drug is determined to be present and detected (true positive) or absent, not detected (true negative). The cut-off value is chosen based on the purpose for which it’s being used e.g. whether for forensic or medical reason.

Ask your doctor about this cut-off level. Is the lab detecting minor amounts of hydrocodone -- then this is normal for codeine metabolism. But if it is detecting a therapeutic dose of hydrocodone, then its presence can't be due to the metabolism of codeine.

Here's a reference for your doctor's use:

http://www.wardelab.com/22-2.html#t1

I hope this helps.

Best wishes with your pain management routine.

[onenanny]

Thank you for this information, I will show it to my PM Dr.