This question is asked by many different people, and for good reason. Marijuana is the most commonly used and tested for drug in the United States and several other countries as well. Marijuana is also the drug that is more likely to stay in your system for days, weeks, or even an entire month after the last time that you smoke. Therefore, even though marijuana is one of the least harmful drugs out there, it is also the most likely drug to cause you to fail a drug test.
When you ask the question “How long does marijuana stay in your system?” you need to take into account the fact that there is no simple answer to this question. Quite simply, it’s argued both that THC never leaves your brain, as well as that there are several different factors which can affect whether or not you test positive for marijuana use.