FEN (Fentanyl)
Fentanyl is a very strong opioid, prescribed as patches or lozenges but also common in illicit pills and powders.
Detection window: Usually detectable in urine for 1-3 days after use, at a 10 ng/mL screening cutoff.
Prescriptions: A valid fentanyl prescription can cause a positive; lab confirmation reports measured levels, which distinguishes a valid prescription.
How Testr tests for it
This panel is part of every Testr visit. A certified collector handles the collection at your home, checks specimen temperature, and reads a clinical 14-panel cassette on the spot. For measured levels rather than a positive/negative read, add laboratory confirmation: a CAP-accredited lab quantifies the result by LC-MS/MS, with measured levels on the report.