What has caused me to fail a drug test I should have passed

failed thc on oral drug test hadnt smoked for 2weeks before and only had 2-3 puffs. I am on asthma medication and nothing else. Had mild dehydration and smoked a cigirette just before test. the amount of time to collect the saliva was prolonged due to a dry mouth and person taking me for the test was unfamilure with the process, test had been recapped before they relised it had to be put under my tounge for 30 secounds as well, after swabing sides of mouth and tounge could the delay time affect the out come of results passed a urine test next morning with a concertrated urine sample had not taken any blockers or anything as I did not know the hospital would drug test me while I was having a dibetic testing done I had told the nurse about the failed test the day before and she tested me without my knowledge if anyone could explain what has happened I would be very thankful cheers
Asked Feb 16, 2013
It can take weeks or even months to get it out of your system
Answered Feb 16, 2013
Excerpt from "The Doctors" website regarding false positives:

Cough suppressants:
•Dextromethorphan, one of three ingredients often found in prescription and over-the-counter cough suppressants, can lead to a positive test for PCP, often called Angel Dust. Taken in higher doses, some cough suppressants can show up as an opiate.
•Pseudoephedrine and ephedra, two other ingredients often found in cough suppressants, can test positive for amphetamines.

Diet pills:
•Phenylpropanolamine, one of the main ingredients in most diet pills, can cause a positive drug test.
•Older diet pills that contain ephedra also can lead to a positive drug test.

•People with chronic pain who use the common over-the-counter painkiller regularly can test positive for THC, the active ingredient in marijuana.

The three substances should be out of your system within 72 hours of taking them. If you get a false-positive result in a drug test, Dr. DiFrancesco says you can request a more comprehensive test.
Answered Aug 18, 2016
You can't escape if you are a drug addict.
Answered Aug 22, 2016

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