A marijuana high from smoking or vaping typically lasts 1 to 3 hours, with some residual effects lingering up to 6 hours. Edibles last significantly longer, often 4 to 8 hours. But “how long does marijuana last” has a second meaning for many people: how long it stays detectable in your body. That answer ranges from 24 hours to 90 days depending on the type of test and how often you use.
How Long the High Lasts by Method
The way you consume marijuana is the single biggest factor in how long you’ll feel its effects. Smoking and vaping produce the fastest onset, hitting within seconds to minutes. The high peaks around 30 minutes after inhaling and then gradually tapers. Most people feel functionally back to normal within 2 to 3 hours, though subtle effects can persist for up to 6 hours.
Edibles follow a completely different timeline. THC has to travel through your digestive system and liver before reaching your brain, which means you won’t feel anything for 45 minutes to 2 hours. In some cases, it can take even longer. Peak blood concentrations arrive 1 to 2 hours after eating, and the full experience can stretch to 4 to 8 hours. This slow onset is why people accidentally take too much: they assume the first dose didn’t work and eat more before it kicks in.
Sublingual tinctures (drops held under the tongue for 60 to 90 seconds) split the difference. Effects begin within 15 to 30 minutes and last roughly 2 to 4 hours. Because the THC absorbs directly into blood vessels under the tongue, it skips the liver processing that makes edibles so intense and unpredictable.
Why the Same Dose Hits People Differently
Two people can smoke the same joint and have noticeably different experiences in both intensity and duration. Tolerance is a major reason. Regular users develop changes at the brain’s cannabinoid receptors that blunt the response to THC. Research on time perception found that frequent users showed dampened effects compared to infrequent users given the same dose, perceiving time more normally while occasional users experienced significant distortion. In practical terms, a daily user’s high fades faster and feels milder than the same dose would for someone who uses once a month.
Body composition matters too, though its effects are more relevant to how long THC lingers in your system than how long you feel high. THC is highly fat-soluble, meaning it gets absorbed and stored in fat tissue throughout the body. People with higher body fat percentages accumulate more THC in those stores, which then slowly releases back into the bloodstream over days or weeks.
The “Weed Hangover” the Next Day
Some people report feeling foggy, slow, or slightly off the morning after using marijuana. The science on this is mixed. A systematic review of next-day effects found that some studies reported impairments in memory, attention, and perception 8 to 12 hours after use. Two older studies using flight simulators even found measurable impairment at the 24-hour mark, though those studies had significant design limitations.
Overall, the evidence for lasting next-day cognitive effects is weak, and the impairments that have been measured tend to be subtle, often showing up only in precise lab tests rather than obvious real-world problems. That said, higher doses and edibles (which process through your body more slowly) are more likely to leave you feeling groggy the next morning than a small amount of smoked cannabis.
How Long Marijuana Shows on a Drug Test
This is where things get complicated, because detection windows vary enormously based on the test type and your usage pattern.
Urine Tests
Urine screening is the most common drug test, and it doesn’t actually look for THC itself. It looks for a metabolic byproduct your liver produces when it breaks THC down. For someone who uses occasionally, this byproduct clears within about 3 to 4 days. For regular users, detection windows stretch dramatically. Chronic daily users have tested positive for up to 24 days after their last use in clinical monitoring, and extreme cases in heavy, long-term users have produced positive results after 77 days of abstinence.
The standard cutoff for a positive urine test is 50 nanograms per milliliter on initial screening, with confirmation testing at a lower threshold. If you use once or twice and then stop, you’re generally clear within a week. If you’ve been using daily for months, expect a much longer window.
Blood Tests
Blood tests detect THC itself, not just its byproducts, so the window is shorter. For occasional users, THC drops below detectable levels within a day or two. Chronic daily smokers, however, can have detectable THC in whole blood for up to 7 days after stopping, because stored THC continuously leaks from fat tissue back into the bloodstream at low levels.
Saliva Tests
Oral fluid testing has the shortest detection window. In controlled studies, THC was found in saliva specimens collected up to about 22 hours after the last dose, but detection rates were low, with only about 2.5% of specimens testing positive at that point. Saliva tests are best at catching very recent use, typically within the last 24 to 48 hours.
Hair Tests
Hair follicle tests have the longest lookback period: 90 days. As your blood supply nourishes hair follicles, drug metabolites get incorporated into the hair shaft as it grows. A standard test takes a 1.5-inch sample, representing roughly three months of growth. Hair tests are designed to detect a pattern of repeated use rather than a single occasion, so a one-time user is less likely to trigger a positive result than someone who uses regularly.
Why THC Stays in Your Body So Long
Unlike alcohol, which is water-soluble and leaves your system within hours, THC clings to fat cells. Your body absorbs it rapidly after use and distributes it into fatty tissue throughout the body, where it can accumulate at higher concentrations than in the brain, liver, or lungs. From there, THC slowly diffuses back into the bloodstream under normal conditions.
This process can be accelerated. Research published in the British Journal of Pharmacology demonstrated that anything triggering fat breakdown (lipolysis) releases stored THC back into the blood at higher-than-normal levels. Stress and fasting are both reliable triggers for fat metabolism. This means that a period of intense dieting or high stress could temporarily spike your blood THC levels days or weeks after your last use, potentially enough to affect a drug test. The researchers suggested this mechanism could explain cases where former users unexpectedly tested positive long after quitting.
This fat-storage dynamic is also why body composition and usage history matter so much for clearance times. A lean person who used once will eliminate THC far faster than a heavier person who used daily for months, simply because there’s less stored THC to work through and fewer fat cells holding onto it.