A THC high from smoking or vaping typically lasts 2 to 4 hours, while edibles can keep you feeling effects for 6 hours or longer. But “wearing off” means different things depending on whether you’re asking about the high itself, subtle cognitive effects the next day, or how long THC stays detectable in your body. Each of those timelines is very different.
Smoking and Vaping: The Fastest Timeline
When you inhale THC, blood levels spike within 3 to 10 minutes. That rapid peak is why the high hits almost immediately. Impairment is strongest during the first hour, then steadily fades over the next 2 to 4 hours. Most people feel functionally normal within 3 to 4 hours of a single session, which is why safety guidelines suggest waiting at least 3 to 4 hours before driving after inhaled cannabis.
Vaping follows roughly the same curve as smoking. The delivery method is slightly different, but THC still enters the bloodstream through the lungs and reaches the brain within minutes. The total duration depends on how much you consumed and your tolerance, but the arc is the same: fast up, peak early, gradual comedown.
Edibles Last Much Longer
Edibles take around 2 hours to reach peak blood concentration, sometimes longer. The delay happens because THC has to pass through your digestive system and liver before it enters circulation. That slow ramp-up is why people sometimes eat a second dose too soon, thinking the first one didn’t work, and end up far more intoxicated than they intended.
The liver also changes THC’s chemistry in a way that matters. When you eat cannabis, your liver converts a much larger proportion of THC into an active byproduct that crosses into the brain more easily than THC itself. This is why edible highs often feel more intense and “body-heavy” compared to smoking the same amount of THC. The ratio of this active byproduct to THC is significantly higher after oral consumption than after smoking.
Total duration for edibles ranges from about 4 to 8 hours, with some people reporting lingering effects even longer. Because absorption from the gut is inconsistent, there’s more variability from person to person and even from one experience to the next with edibles than with inhaled cannabis.
What Tolerance Does to Duration
If you use cannabis daily, the high from the same dose will feel shorter and weaker over time. This isn’t because your body is clearing THC faster. In fact, the opposite happens. A study of daily cannabis smokers given high oral doses found that blood levels of THC and its active byproduct actually increased over six days of repeated dosing. Despite rising THC in their blood, the participants reported feeling less intoxicated by day 4 and 6 compared to day 2.
The explanation is receptor-level tolerance. The brain’s cannabinoid receptors gradually dial down their responsiveness with repeated exposure. Brain imaging studies have confirmed this downregulation in chronic users. Different brain regions adapt at different rates, which is why some effects (like appetite changes) may fade faster than others (like memory disruption) with regular use. For a daily user, a single session might produce a noticeable high for only 1 to 2 hours, while the same dose could affect an occasional user for 3 to 4 hours.
The “Cannabis Hangover” Question
Some people report feeling foggy, sluggish, or slightly off the morning after using cannabis. The scientific evidence for this is mixed. A systematic review of next-day effects found that most studies, including the higher-quality ones, showed no measurable impairment beyond 8 to 12 hours after use. A small number of studies did find subtle effects on perception, divided attention, and memory in that 8 to 12 hour window, and two older flight simulator studies detected impairment as far out as 24 hours after a roughly 20 mg THC dose.
Overall, the research suggests that if a cannabis hangover exists, it’s mild. The same review noted that a THC hangover is “unlikely to be more impairing than an alcohol hangover,” which most people consider manageable enough for normal daily activities. That said, higher doses and edibles are more likely to leave you feeling off the next morning than a small amount of smoked cannabis.
How Long THC Stays Detectable
Feeling sober and testing clean are two completely different timelines. THC is fat-soluble, so it gets stored in body fat and released slowly over days or weeks. The plasma half-life of THC is 1 to 3 days in occasional users and 5 to 13 days in people who use it daily. About 80% to 90% of a dose is excreted within 5 days, mostly as breakdown products in urine and stool.
Urine Tests
Urine testing is the most common screening method, and the detection window depends heavily on how often you use cannabis. A single or occasional session is typically detectable for up to 4 days. Moderate use extends that to roughly 1 to 2 weeks. Daily or near-daily use can produce positive results for up to 24 days, and some heavy, long-term users have tested positive even longer.
Blood and Saliva
Blood tests detect THC for a shorter window, generally 1 to 2 days for occasional users. THC in saliva follows a similar timeline, often detectable for 24 to 72 hours. These tests are more useful for measuring recent impairment, which is why roadside testing programs tend to use saliva.
Hair Tests
Hair analysis provides the longest detection window: up to 3 months. However, hair testing works best as an indicator of heavy, daily or near-daily use. It is less reliable for detecting occasional or one-time cannabis use.
Factors That Speed Up or Slow Down the Process
Several variables influence how quickly THC’s effects fade and how long it lingers in your system:
- Dose: Higher doses produce longer, more intense effects and take longer to clear. This is straightforward but worth stating because the difference between 5 mg and 50 mg of edible THC isn’t just intensity; it’s hours of additional duration.
- Frequency of use: Regular users accumulate THC in fat tissue, which extends detection times dramatically. But paradoxically, tolerance means they feel the high for a shorter period than an occasional user taking the same dose.
- Body composition: Because THC is stored in fat, people with higher body fat percentages may retain detectable THC longer. This primarily affects drug test timelines rather than the duration of the high itself.
- Metabolism: Individual metabolic rate affects how quickly your liver processes THC. Faster metabolism generally means a shorter high and quicker clearance, though this varies enough from person to person that it’s hard to predict.
- Method of consumption: Inhaled THC enters and exits the bloodstream faster. Edibles produce a slower, longer experience because of delayed absorption and greater conversion to THC’s potent active byproduct in the liver.
For practical purposes, if you smoked or vaped a moderate amount, you can expect to feel normal within 3 to 4 hours. If you ate an edible, give it 6 to 8 hours. And if you’re concerned about a drug test, the answer depends almost entirely on how often you use: a few days for a one-time session, potentially a month or more for daily use.