A 23-year-old male asked:

Hi doctor, i started smoking weed since 25 days,before that i only used to smoke cigarettes. but now i have started running 3 km daily. so can u please tell me approximate days my body will take to pass the urine or blood test. thanks?

1 doctor answer4 doctors weighed in
Dr. Alan Wartenberg
A Verified Doctoranswered
Addiction Medicine 51 years experience
Hard to be sure: because it depends on HOW MUCH weed you smoked and HOW POTENT it was. The use of very high potency marijuana for 3 weeks, if you were smoking it all day every day, can cause positive urine tests for literally a month or even longer (longest I have seen is 3 months). Hair testing can detect it back for 6 months or longer, depending on hair length and type. Low level use lasts for 3-7 days.
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Last updated Jan 3, 2016


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