What exactly are Fentanyl Test Strips?

This type of test is called a “lateral flow competitive immunoassay”, and it’s pretty much the reverse of a rapid COVID test or pregnancy test. The strip is pre-loaded with “control particles” and when you dip it into your sample, the water carries these particles along with the drug towards the testing lines.
If there’s no fentanyl, the control particles will bind to the testing line, causing it to become visible, but if there is Fentanyl, it will bind instead and the line won’t appear.

There is a QR code on the back of the back that users can scan and it will take them to the Dosetest website and walk them through the steps to test their sample. You can also download a PDF copy of the instructions from the Link tab for this product and hand it out to customers if required.