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Family Physician
Family Physician, Doctor (MD)
Category: Health
Satisfied Customers: 12816
Experience:  Emergency Medicine and Family Practice for over 26 years
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how far back can a swab drug test detect

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how far back can a swab drug test detect
What kind of swab test are you taking about?

Customer: replied 8 years ago.
a swap for saliva for like marijuwana and stuff like that
Sorry i need to opt out of your question.

Customer: replied 8 years ago.
what do u mean opt out my question
I'm sorry, the other expert was unable to answer your question:

The length of detection for saliva is generally shorter than urine or hair testing.

One study reported the detection periods for various drugs in saliva;
Marijuana 34 hours
Cocaine 24 hours (up to 10 days in chronic users)
Amphetamines up to 50 hours
Customer: replied 8 years ago.

will it help if i use exesive mouth washing and tooth brushing before the test for marijuana?it's 6 pm right now and my test is at 5:30 am tomorrow ?


NO - there is no evidence that mouth washes and/or brushing your teeth repeatedly will reduce the detection time. The marijuana metabolites tested for with these test are stored in the body fat and released slowly. This approach will not work.

Likewise - you may find various products claiming to "flush" or "cleanse" the body of drugs for drug testing. NONE of these products actually work and some of them may be dangerous if used as directed.
Customer: replied 8 years ago.

yes but it's a mouth swab wouldnt exsesive mouth washing and tooth brushing right before the test do something?

There is no good evidence that this would be effective in causing what would be a positive test to be negative.
Customer: replied 8 years ago.
ok well my boss says that it's usually 6 to 8 hours prior to the test and they were saying that what u do at home is ure perogative they just dont want it at work thats why they only do it in the morning before work. but howcome u told me 34 and there saying 6 to 8 hours should i believe that ? im just trying to be on the safe side .
The sensitivity of the test being used by your employer may be less than the sensitivity of the test used in the published reports.
Customer: replied 8 years ago.
as in like it might not go as far back as the common swab ?
Correct - each test has a sensitivity (the amount of drug or drug metabolite) that needs to be present before it is detected. A less sensitive test would need a higher drug level to be reported as positive - and therefore a shorter detection period.
Customer: replied 8 years ago.
so thats why i was asking cuz that might be the case that they just want to make sure ure not doing it before work and stuff like that right
Again - without knowing the exact details of the testing methods (including the specific sensitivity of the test) it would be impossible to state how long it may be detected.

The important question is there anything you can do; NO - you just have to cross your fingers and hope that the test is not that sensitive.
Customer: replied 8 years ago.
well u did say 34 hours it will be 33 for me tomorrow when i get it so what would be your opinion on that?
The time varies depending on the dose, frequency of use and other factors. In your case - at 33 hour there is a good chance that yours would be negative, particularly if the test is not one of the high sensitivity tests.
Family Physician, Doctor (MD)
Category: Health
Satisfied Customers: 12816
Experience: Emergency Medicine and Family Practice for over 26 years
Family Physician and 4 other Health Specialists are ready to help you