marijuana how long does it stay in your urine
Some THC metabolites have an elimination half-life of 20 hours. However, some are stored in body fat and have an elimination half-life of 10 to 13 days. Most researchers agree that urine tests for marijuana can detect the drug in the body for up to 13 days. However, there is anecdotal evidence that the length of time that marijuana remains in the body is affected by how often the person smokes, how much he smokes and how long he has been smoking.
Hereâs What the Research Shows. 1  One key study found that weed can stay in a personâs urine for a surprisingly long period of time. 2  1-time use will usually stay in your system for 5-8 days. 3  If you use cannabis 2-4 times per week and then stop, youâll test positive for 11-18 days. If you smoke 5-6 times per week, itâll stay in your urine for 33-48 days. And if youâre a serious smoker who gets high every day, weed will stay in your urine for 49-63 days.