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"I took a saliva drug screen test. I don't do any drugs, but I'm not worried. How does it work?"

ZocdocAnswersI took a saliva drug screen test. I don't do any drugs, but I'm not worried. How does it work?


Only thing that bugs me is that when I take the test out of my mouth it's red kind of and others are blue .why? They send it out to quest for labs on drugs ..


There are many different drug tests that are available, and each will have different methods and changes that will happen in the presence of certain drugs and medications. I recommend that you speak with your doctor about your question. If you are not taking any drugs or other medications that could cause these changes, you likely have nothing to worry about despite any changes that you may have seen. Any test, however, can have both false positives and false negative results. A false positive result would be when the test says that you do have something that is not real. In this case, a false positive test result would suggest that you ARE taking certain illicit drugs, when you in fact are not. A false negative test result would be the opposite, of course. If you were taking an illicit substance, a false negative would not show that you were. In either case, the result is obviously a problem. Because all tests have both some false positives and some false negatives, doctors have to pick the test that they are using carefully and in the context of other information. Employers are not necessarily required to do that, although follow up testing may be indicated. Again, please speak with your doctor more about this.

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