How long a high lasts depends almost entirely on what substance produced it. A cannabis high from smoking typically fades within two to three hours, while an edible can keep you elevated for six to eight. A cocaine high may burn out in 30 minutes, while methamphetamine can last up to 12 hours. Below is a practical breakdown by substance, along with the biological reasons some people feel effects longer than others.
Cannabis: Smoking vs. Edibles
Smoking or vaping cannabis produces the fastest onset, usually within minutes. The peak hits quickly, and the full experience generally wraps up in one to three hours. Most people feel functionally normal again within about three hours of their last inhale, though mild grogginess can linger.
Edibles are a different story. They typically take 30 to 60 minutes to kick in because THC has to pass through your digestive system and liver before reaching your brain. Peak blood levels don’t arrive until about three hours after you eat one. The total high generally lasts six to eight hours, and some residual heaviness can stretch into the next morning. This delayed onset is why people sometimes eat a second dose too early, stacking effects that become uncomfortably intense.
Alcohol
The “buzz” from alcohol sets in within 15 to 45 minutes of your first drink, depending on whether your stomach is empty. How long it lasts is a matter of math: the average body clears alcohol at a rate of about .015 to .020 BAC per hour. That means someone who reaches the legal driving limit of .08 BAC needs roughly four to five hours to return to zero. Two or three standard drinks on a full stomach might produce a buzz that fades in a couple of hours, while a heavier night of drinking can leave you impaired well into the following day.
Cocaine and Methamphetamine
Cocaine produces a sharp, intense rush that fades fast. Snorted cocaine typically lasts 15 to 30 minutes, and smoked crack cocaine is even shorter, often under 15 minutes. This rapid drop-off is a major reason people redose frequently, which drives the risk of overdose and cardiovascular problems.
Methamphetamine targets many of the same brain pathways but sticks around far longer. Its effects can last up to 12 hours depending on how it’s used. Smoking or injecting produces a faster, more intense onset, while swallowing it delays the peak but extends the overall duration. The long tail of stimulation often makes sleep impossible for a day or more, which compounds the physical toll.
MDMA (Ecstasy)
MDMA’s primary effects last four to six hours. Most people feel the onset within 30 to 45 minutes: a building sense of warmth, energy, and emotional openness. The peak plateau holds for two to three hours before gradually tapering. After the main effects fade, a comedown period often follows, marked by fatigue, low mood, and difficulty concentrating. This can last a day or two, and in heavier users, sometimes longer. The comedown happens because MDMA floods the brain with feel-good signaling chemicals, temporarily depleting stores that take time to replenish.
LSD and Psilocybin Mushrooms
Psychedelics sit at the long end of the spectrum. Both LSD and psilocybin mushrooms take about an hour to kick in on an empty stomach. From there, the experiences diverge in length.
A mushroom trip usually closes within six hours. The peak tends to arrive around two to three hours in, then gradually softens. LSD lasts considerably longer, with a full trip stretching up to 10 hours. This is worth knowing before you commit to the experience: an LSD trip that starts at noon may not fully release you until late evening. Both substances can leave a mild afterglow, a subtle shift in mood or perception, for several hours after the main effects end.
Why Duration Varies From Person to Person
Two people can take the same substance at the same dose and have noticeably different timelines. The biggest factor is how quickly your liver processes the substance. Liver enzyme activity varies widely based on genetics. Some people carry gene variants that make them fast metabolizers, clearing drugs quickly. Others are slow metabolizers who feel effects at lower doses and for longer periods.
Age plays a measurable role. As you get older, the liver’s processing capacity drops by 30% or more because both liver volume and blood flow decline. This means the same dose hits harder and lingers longer in older adults compared to younger ones. At the other extreme, newborns and very young children have immature liver enzyme systems that process substances slowly, which is one reason accidental ingestion in children can be so dangerous.
Body composition matters too. Many psychoactive substances are fat-soluble, meaning they get absorbed into fatty tissue and released slowly over time. People with higher body fat percentages may experience a slightly extended tail of effects, particularly with cannabis. Hydration, food intake, and overall liver health (especially conditions like chronic liver disease or heart failure) also shift the timeline in meaningful ways.
Quick Reference by Substance
- Smoked/vaped cannabis: 1 to 3 hours
- Cannabis edibles: 6 to 8 hours
- Alcohol: roughly 1 hour per standard drink to clear
- Cocaine (snorted): 15 to 30 minutes
- Methamphetamine: up to 12 hours
- MDMA: 4 to 6 hours
- Psilocybin mushrooms: up to 6 hours
- LSD: up to 10 hours
These are averages. Your actual experience will shift based on dose, tolerance, body chemistry, and whether you’ve eaten. Higher doses don’t just intensify the experience, they extend it, sometimes significantly.