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Faint lines on drug test results and what to do about them


According to ALL of the manufacturers, the faint line is always interpreted as negative.  And it doesn’t matter how faint the line is -- If you can see a line (even the ghost of one) you have to interpret it as negative.

Remember to always follow the manufacturers' instructions found in the product insert. Most drug test results are to be interpreted at 5 minutes, not after. Lines can change in color and intensity over time due to evaporation and other factors. Keep to the time frame specified.


In short, a line forms when the metabolite screened for is below the detection threshold or "cut-off level," the industry-standard minimum that allows for drug detection with minimal interference from cross-reactant substances.

Any line visible to the naked eye is to be interpreted as negative. You cannot draw conclusions from line differences.

Please contact us @ 888-562-5852 if you have any questions.