Will diphenydramine 50 mg show up as methadone

Question

i have never takin methadone but failed a urine test for it.  i do take 200 mg a night.

Answer 1

It may show up as a false-positive, depending on the type of test performed.

Typically rapid urine drug screens using immunoassays based on the principle of competitive binding may show false-positive methadone results for patients who have taken DPH. Product information for urine drug screens may not include all cross-reacting agents and should be used with caution when interpreting drug screen results in PED patients.

Please see http://www.ncbi.nlm.nih.gov/pubmed/20838187