Last Updated on by Dr. Ronaye Calvert-Conley
How long does weed stay in your system? Specifically let’s look at How long it stays in your blood, urine and hair.
Weed, or marijuana, is currently the most commonly used illegal substance in the world. Many countries are making moves towards legalizing the drug and some countries have already done so. Even though the effects of Marijuana can be short lived, weed can remain in the system for a number days after you smoke it.
Marijuana or weed can stay in the urine up to 45 days
Marijuana can stay in the blood up to 75 days
Marijuana can stay in the hair follicles up to 90+ days
- Exactly How Long Does Marijuana Stay in Your System?
- What Is THC and How Long Does THC Stay in Your System?
- How Long Does Marijuana Stay in Your Urine?
- How Accurate Are Urine Test Results for Marijuana or THC?
- What Is the Best Way to Pass a Urine Test for Marijuana?
- The Final Word on How Long Does Weed Stay in Your System?
Exactly How Long Does Marijuana Stay in Your System?
Marijuana has had many uses over the centuries humans have been using it. It comes from the leaves, stems, flowers, and seeds of the Cannabis sativa plant.
When used medicinally it can help to ease pain, nausea, inflammation, and some chronic conditions.
How you are affected by marijuana depends on many factors, and the high can be different for you each time you experience it. For example, if you’re smoking marijuana while you’re surrounded by angry or agitated people it may not have the calming effect you might experience when you smoke it at home on your own.
Although the effects of marijuana may fade quickly the substance can stay in your system for considerably longer. It largely depends on how much marijuana you have used and how you used it.
What Is THC and How Long Does THC Stay in Your System?
THC (tetrahydrocannabinol) is the active ingredient in marijuana. Essentially, it’s the part that gets you high, gives you the munchies, and may make you feel paranoid. If it’s smoked it will enter your bloodstream very quickly. If it’s ingested it may take anywhere from 20 minutes to 1.5 hours to produce an effect.
Short-term effects from using marijuana – such as memory loss, coordination, and problem-solving will usually ease after one or two hours. Some minor effects may linger for up to 24 hours.
THC itself is only detectable in your bloodstream for a few hours. This is because it breaks down into metabolites quickly. Metabolites are stored in body fat and eventually leave the body through urine and feces.
Some metabolites have a half-life of 20 hours. This means that in 20 hours, only half of the marijuana is still in your system. However, many metabolites that are stored in body fat have a half-life of 10 to 13 days.
Find out more on the symptoms of marijuana addiction
For marijuana to be completelyout of your system it can take up to 5 to 6 half-lives.
How Long Does Marijuana Stay in Your Urine?
Most researchers agree that marijuana can be detected in urine for up to 13 days. However, there is some disagreement about whether smoking or ingesting the substance eliminates it from your body quicker.
Marijuana has been detected in some regular smokers at 45 days after last use. It has also been detected in heavy smokers at 90 days out from their last use.
How Accurate Are Urine Test Results for Marijuana or THC?
Urine tests are far more accurate now than they used to be.
The urine undergoes an immunoassay test. If those results are positive, next the laboratory will perform another screening with a gas chromatograph mass spectrometer (GCMS). Because two separate tests are performed, false positive results rarely occur.
Contrary to popular myth, drinking a lot of water and urinating before a test will not eliminate all the THC from your body. Some herbal teas are marketed as eliminating marijuana from your body but there has been no conclusive research conducted that proves that.
You may have heard about chemicals being introduced to urine samples as a way of contaminating the urine tests to help you pass. This may be possible, but laboratory staff who perform these tests every day are easily able to tell when a sample has been contaminated.
What Is the Best Way to Pass a Urine Test for Marijuana?
The only foolproof way to pass a urine test for marijuana is to stop using marijuana before the test takes place. There is no way to make it leave your system quicker and there are no substances you can take that will give you a false, clean, result.
Driving while under the influence of weed, or marijuana, is illegal. This is true even in the countries that have legalized its medicinal or recreational use.
Studies have suggested that using marijuana can impair your driving for up to 3 hours after smoking marijuana. Even though you may feel as if you are perfectly able to drive, your reactions will be considerably slower than normal.
The Final Word on How Long Does Weed Stay in Your System?
There is no definitive answer to the above question, but it is certainly true that marijuana stays in your system long after you have stopped feeling the effects of it.
It is best to only utilize marijuana for medicinal purposes.
Dr. Ronaye Calvert-Conley is the CEO and Founder of Revive Detox, a Joint Commission Accredited and Legit Script Certified Addiction Treatment Center in Los Angeles, CA. She earned her Doctorate in Clinical Psychology from Alliant International University in Los Angeles in 2007 and has extensive experience working in the addiction and recovery field and the LGBT community. To learn more about Dr. Calvert-Conley click here.