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A 51-year-old female asked:

How long can marijuana be detected in saliva after usage. smoked 12 days ago and have saliva swab for employment tomorrow.

2 doctor answers4 doctors weighed in
Dr. Alan Wartenberg
A Verified Doctoranswered
Addiction Medicine 51 years experience
Short time for 1 use: If it was a single use 12 days ago, it is unlikely that the test will be positive, and usually is negative within 72 hours. However, if you were a regular smoker, thc metabolites are soluble in fat, and tests (both urine and saliva) can remain positive for weeks and even months. If it was occasional use (once a week or less), it will most likely be negative. Am concerned about your risking ur job!
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Dale Rottman
Dentistry 46 years experience
Not long: Marijuana in the saliva is only detectible for a short time, probably 6-8 hours if smoking. If you are eating it, it could last longer. If a urine test is being done, the effects of marijuana could last up to 45 days.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Jul 3, 2017


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