There are a few different ways to test for THC and other drugs in the human body. The most common method of testing people for drugs in their system is by analyzing their urine. Whether searching for THC itself or simply metabolites of THC, which indicate THC was consumed recently, drug tests can be pretty damn good at what they do. Besides urine tests, there are also saliva, hair follicle, and blood tests to worry about. A blood test is pretty rare and is generally used to detect whether someone has recently been heavily impaired by marijuana. So how long does weed stay in your system before you can pass a blood test with flying colors?
It Depends
Before giving you the generally agreed-upon estimate of how long THC and THC-related metabolites stick around in your blood, here’s a little reminder of all the different biological factors which can affect this.
- Your individual metabolism. The rate and efficiency at which you digest food.
- The amount of cannabis you consume and how frequently you consume it.
- The parameters of the particular blood analysis test. This can vary depending on the purpose.
- BMI or body mass index.
- Whether the test is aiming to detect THC itself or metabolites of it.
- The method of consumption. Vapor and smoke are quite similar, but edibles take the longest by far.
With all that being said, cannabis generally remains detectable in blood for only about one or two days after a single use, whereas it can take up to seven days for heavy users. Even the most chronic of stoners, detection after more than a full week is rare and would certainly result from the aforementioned factors.
Why So Little Time Compared To Urine?
How long does weed stay in your system for a urine test instead? For heavy smokers who take up multiple times per day, it can actually take up to 80 days of abstinence to pass a drug test. This is due to testing a wider range of metabolites that show up in your urine on their way out of your body. Since THC tends to store itself in your fat cells, it doesn’t stick around for very long in your bloodstream, but you bet it will stick around in other places. When you pee, you’re disposing of waste from all the other systems in your body as well, and so that’s why it can take so much longer to test clean for a urine analysis.
