Every year, the U.S. Department of Transportation conducts over 6 million drug and alcohol tests. Marijuana—also known as pot, weed, or herb—is often a key focus. It’s no surprise many people wonder, “how long does weed stay in your system?” While the answer depends on several factors, science has helped us understand it much more clearly.
Marijuana is made up of more than 100 chemical compounds called cannabinoids, but the two most well-known are THC (tetrahydrocannabinol) and CBD (cannabidiol). THC is the compound that creates the “high” people experience, while CBD doesn’t cause any psychoactive effects and is often valued for its potential health benefits.
When you consume marijuana, THC and CBD enter your bloodstream and interact with the body’s endocannabinoid system—a network of receptors that helps regulate mood, appetite, pain, and other functions. How long and how strongly you feel these effects can vary depending on factors like dosage, how you consume it, and your personal sensitivity to cannabinoids.
THC is the main compound in cannabis that standard drug tests look for. Detection times for THC can vary based on usage:
While the “high” from marijuana usually lasts just a few hours, THC and its byproducts can stay in your system much longer. This matters for drug testing because a positive result doesn’t always mean someone is currently impaired.
CBD can remain in your system for up to about a week after use, though factors like how often you use it and your individual metabolism can affect how long it lasts.
After entering the bloodstream, THC is quickly processed by the liver into a compound called 11-hydroxy-THC, which then breaks down into several inactive metabolites, including THC-COOH. These metabolites are stored in body fat and slowly leave the body through urine and feces. How fast this happens varies based on individual factors like metabolism and body composition.
Several personal factors can influence how long marijuana stays in your system:
The type of marijuana you use doesn’t change how long it stays in your system, but it does affect how long the “high” lasts. When smoked, marijuana usually peaks around 30 minutes after use. Edibles, however, are absorbed more slowly through the digestive system and can take up to 3 hours to reach their peak effects.
Urine tests are the most common way to detect marijuana use. These tests mainly measure THC-COOH, an inactive byproduct of THC that can stay in your urine for a long time. Detection times depend on factors like how often you use marijuana:
Blood tests are less common than urine tests because they’re more invasive and have a shorter detection window—usually around 2–7 days.
Unlike urine tests, which measure the inactive metabolite THC-COOH, blood tests detect the active THC still circulating in the bloodstream. Once THC is processed by the liver, it quickly converts into THC-COOH, which is stored in body fat and slowly eliminated through urine.
Hair follicle tests can detect THC and its byproducts for much longer than urine or blood tests because these compounds get deposited in hair as it grows. Using this method, marijuana can be detected in your system for up to 90 days.
Saliva tests are the most effective way to detect recent marijuana use or impairment. They’ve become more popular because they’re non-invasive and can quickly identify recent consumption.
Marijuana can usually be detected in saliva for 5–48 hours after use, with the highest levels appearing in the first few hours. Law enforcement increasingly uses saliva tests for roadside checks, as they provide a fast and reliable way to spot drivers under the influence.
It’s unlikely that a single hit of weed would stay in your system for more than a few days. On average, THC from a single use is eliminated in about 42 hours. Depending on several other factors like metabolism and body composition, it can sometimes be detected for up to 3–4 days.
Some people try to beat a drug test by diluting urine, using synthetic samples, or taking detox products. However, these methods are often unreliable and can be very risky. Trying to cheat a drug test also doesn’t support recovery and may carry serious legal consequences. The safest and healthiest approach is to seek help, abstain from drug use, and prioritize your well-being.
If you’ve ever considered faking a test or are asking yourself, “is marijuana addictive?”, reaching out for support can help you understand and overcome marijuana dependence.
Detoxing from marijuana can take anywhere from a few days to several weeks. For most occasional users, THC can be detected for about 3–7 days, while chronic users may test positive for up to 3 months.
When it comes to how long cocaine stays in your system, it’s usually detectable in urine for about 2–4 days after use. However, its metabolites can linger longer—sometimes for several weeks. The exact detection window depends on factors like how much and how often it was used, metabolism, and individual differences.
If you’re wondering how long ecstasy stays in your system, MDMA can usually be detected for about 2–4 days. During this time, traces may show up in urine, blood, or saliva. Keep in mind that factors like your metabolism and the amount taken can affect how long it remains in your body.
Wondering how long heroin stays in your system? Typically, heroin can be detected for about 2–3 days in urine, blood, or saliva. The exact length depends on factors like dosage and your body’s metabolism.
If you’re asking how long meth stays in your system, methamphetamine can usually be detected for 2–4 days, though in some cases it may show up for up to a week. How long it lingers depends on factors like the amount used, your metabolism, and the type of drug test.
Wondering how long alcohol stays in your system? It depends on factors like how much you drank and your metabolism. On average, alcohol can be detected in urine for up to 48 hours and in blood for around 12 hours. Keep in mind that heavy drinking can extend these detection times.
If you’re asking how long Xanax stays in your system, this anxiety medication usually remains detectable for about 4 days. After taking it, tests such as urine or blood screenings can identify it for up to four days.
Wondering how long Suboxone stays in your system? Detection times can vary. Suboxone may show up in urine tests for several days or even longer, while its effects can last beyond that. Naloxone, one of its components, typically leaves the system faster—usually within about a day.
If you’re asking how long fentanyl stays in your system, it and its byproducts can usually be detected in urine for about 1–2 days. The exact detection time can vary based on factors like dosage, how often it’s used, your metabolism, and the type of drug test.
Wondering how long opioids stay in your system? The answer depends on the specific opioid, dosage, your metabolism, and the type of drug test. In general, most opioids can be detected in urine for about 2–4 days, though some with longer half-lives may remain detectable for a longer period.
If you’re asking how long Ambien stays in your system, the medication (zolpidem) usually remains active for about 8 hours, after which its effects wear off. However, it can sometimes be detected in urine for up to 72 hours, depending on factors like dose, how often it’s taken, and your metabolism.
If you’re wondering how long methadone stays in your system, it’s usually detectable in urine for about 7–10 days after your last dose. The exact time can vary based on factors like metabolism and how frequently it’s used. In some cases, methadone can even be detected in hair follicles for several months.
If you’re asking how long Percocet stays in your system, it can generally be detected in urine for about 3–4 days after your last dose. The exact timeframe can vary depending on factors like your metabolism, the dosage taken, and the sensitivity of the drug test.
