The effects of smoking marijuana fade quickly, but the drug, known affectionately as "weed," can be detected in the body for weeks and sometimes longer. How long it remains in the system depends on how often or how much marijuana the user has been smoking.
Philly said:There is many factors it depends on, mainly how much you smoke/smoked.
Jason said:It can also vary from strain to strain depending on the strain's percentage of THC.