What does a faint line on a drug test mean?

What does a faint line on a drug test mean?

faint line drug test

How do I read a faint line on a drug test kit

This is a common question and one that can cause a lot of confusion and anxiety

On the picture above, you can see a drug test result using a saliva drug test which has tested for 4 drugs: COC Cocaine, AMP Amphetamine, OPI opiates, and THC Cannabis. The C is the control line to show that the drug test membrane has absorbed enough saliva to run the test.

You can see on this test kit that the lines vary in intensity but that there is a test line present for each drug. The THC and the OPI lines are fainter than the others in this particular test.

All of these drug test results including the faint lines are negative ie no drug was detected

The THC line on the test strip on the bottom left of the photo is very faint in this case, but this is still a negative result. The faintness of the THC test line is of no significance and should not be interpreted in any other way than as a negative result.

More information on what a faint line on a drug test means and how to read it 

Please contact our UK Drug Testing customer support team if you need any further help or advice.

You may also find this video on interpreting a faint line on a drug test helpful

 Take our drug test quiz if you would like to find the best drug test kit for your needs

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Adam how did your blood test results come back because I yesterday was in the same situation I had a faint kind and hadn’t taken anything for over a week


I took a home urine THC test and had a faint line on the control and no one on the test. What does that mean?

Brian Starks

I had a faint line , it was that faint on the test the police had to use a phone light behind the test to see it , I couldn’t personally see it but I still got arrested , is this a positive or negative ? As I feel like I’ve been done for something I should of been passed on thanks


A line is a line. If it’s faint, it’s still there. They may swab again to confirm, but they are just doing that because they don’t know any better. A p.o. will toss it in the trash and send you about your day with a faint line


You may find this information page helpful it explains how to interpret faint lines on drug test results https://www.ukdrugtesting.co.uk/pages/faint-line-on-drug-test

UK Drug Testing

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