There is no definite answer to this question, since no one can say exactly how long marijuana stays in your system. The length of time varies significantly from person to person.
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How Marijuana Enters and Leaves Your Body
Marijuana contains over 400 chemical compounds called cannabinoids. One of them is tetrahydrocannabinolic acid (THCA) contained in fresh, undried plants. It is decarboxylated to delta-9-tetrahydrocannabinol (THC) when plants are dried, and especially when they are exposed to high temperature, such as when marijuana is smoked, vaped or cooked into edibles.
When you smoke, THC enters your body through respiratory tract, processed in lungs (or in stomach, if you eat edibles) and absorbed into the bloodstream, where it is carried to the brain and other organs. When getting to brain’s neurons, THC binds to the CB1 and CB2 receptors of your endocannabinoid system. This starts euphoric effects in your brain.
After reaching the liver, THC is metabolized into THC-COOH (11-nor-9-carboxy-Δ9-tetrahydrocannabinol), which is inactive substance. It goes to kidneys with bloodstream, from where it is excreted out of the body with urine. The withdrawal process may cause several symptoms, such as: cravings for marijuana, mood changes, irritability, anxiety, depression, headaches, sleep problems, diminished appetite and others.
Why It Is Not Easy to Predict How Long It Stays in the Body
Online THC Calculator |
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calculates the level of thc in urine based on smoking over a specific period of time |
The approximate half-life of marijuana metabolites in the human body is 7 days, and THC calculator based on this index shows the average dynamics of the reduction of the THC level in the human body over time. It cannot predict how long weed stays in your body. It only shows the approximate daily THC levels of the average person.
How to Determine the Time THC Stays in Your System
You can still determine your personal time by testing yourself. Buy a few home drug tests, stop smoking pot, and test yourself every day until you get a negative result. Doing this will show how long marijuana stays in your system, but do not forget that the length of time may also vary depending on various factors.
Key Influencing Factors
- Amount and potency of marijuana. Obviously, the more you smoke, the more toxins will saturate your body, and the longer it will take to flush them out.
- Frequency of smoking. Building on the above point, the more often you smoke marijuana, the longer it will take for your body to rid itself of toxins. The occasional smoker will be able to eliminate the THC much faster than a frequent smoker, but a strange phenomenon affects chronic smokers. You would expect that they would have the longest detection time and the smallest chance of passing a drug test, but this is not always the case. Chronic smokers with a high drug tolerance sometimes eliminate toxins more quickly than occasional smokers.
- Personal metabolism. Fast metabolism lets the body naturally flush marijuana at an accelerated pace.
- Age. This factor is closely linked to metabolism, which is usually slowing due to aging. Generally speaking, the younger you are, the faster your body will detoxify itself.
- Weight. THC is stored in fat cells, so the less fat a smoker has, the less THC accumulates in his body. Also, skinny people usually have faster metabolism, which lets them get rid of toxins faster.
- Lifestyle. Physical activity burns fat and accelerates metabolism, so weed stays in the body of active people for a relatively shorter period of time compared with someone who is inactive.
- Fluid intake. Urination is highly important for cleansing the body of waste. Drinking fluids speeds up urination and flushes THC metabolites from the body.
Does Method of Consumption Impacts Marijuana Detection Time?
Yes, the method of consumption impacts at how long marijuana stays in your system. After smoking or vaping, the THC concentration in your body drops faster than after ingesting, because edibles must be digested in the stomach to enter your system, and this takes longer time than inhalation through the lungs. The difference, however, is not big. It can range from several hours to one day, but this time can be very important for those who need to pass a drug test on short notice.
How THC Is Detected in Your System
THC in the body of user can be detected using analysis of biological samples, such as urine, blood, saliva, etc. Urine test is the most common. It is a two stage process. In the initial test, enzyme-multiplied immunoassay technique (EMIT) is used. If it comes out positive, sensitive laboratory equipment used for gas chromatography–mass spectrometry (GC-MS) testing to confirm the result.
The initial test is considered positive if the level of THC-COOH in urine is above 50 nanograms per milliliter (ng/mL). This threshold is called cutoff level. In case of confirmation testing, it is set at 20 ng/mL.
How Long Can Weed Be Detected in Various Drug Tests?
Different methods are used to detect marijuana in the human body. You can check urine, hair, saliva, blood, or sweat, but the length of time that THC is present in all these substances after smoking varies significantly, so every drug testing method has a different time range for detecting marijuana.
- Urine. This test is the most common method of detection, and the aforementioned key factors strongly influence marijuana detection time in urine. For those who have smoked weed only once, the detection time is usually from 2 to 6 days. For moderate smokers, it is 1 to 2 weeks. Frequent users can test positive for more than 2 weeks, and in rare cases marijuana can stay in the system of heavy smokers for more than a month.
- Hair. This kind of test is less common, and key factors do not have any impact on detection time. This test is the only one that cannot detect recent drug use, since hair needs time to grow. This is why you can test positive only starting from about one week after use. Traces of marijuana stay in the hair follicles for up 90 days, and hair from not only the head but also other parts of the body can be used as a sample.
- Saliva. This test has the shortest detection time period. It is intended to detect only recent drug use and can detect marijuana for only the first few hours after smoking, with a maximum of 24 hours.
- Blood. THC also does not stay in the blood for a long time, just up to 24 hours. Blood testing is not common because it is invasive, so a saliva test is preferable in most cases for detecting recent smoking of pot.
- Sweat. This test is the rarest because the procedure for collecting samples is complicated, where a sweat patch is worn over the time. Marijuana can be detected in sweat for 1 to 4 weeks after use.
How to Clean Your System from Marijuana and Reduce Detection Time
If marijuana stays in your system for a long time, removing it can be accelerated. For example, exercise and increased fluid intake are helpful, since these are among the main factors influencing the detox process, but these methods cannot be recommended for passing a urine test, since exercise releases toxins from fat into the bladder, thus temporarily increasing the level of THC metabolites in the urine, and excessive drinking makes urine look diluted, which leads to rejection of the sample.
If you need to prepare for a drug test, there are effective detox solutions available that will cleanse your system from marijuana upon short notice. For a hair test, detox shampoo must be used. For a saliva test, detox mouthwash is used, and detox drinks and pills are used for a urine test.
This best-selling detox kit will help you eliminate marijuana from your system and pass a drug test upon short notice. It includes the Herbal Clean QCarbo detox drink, QChew supplement, and a home THC test device to confirm the effectiveness of the cleansing process.
For more detailed information about how to pass a drug test and selecting the right method for your needs, please read the following articles: