According to the latest research, you will stay high between three to ten hours after consuming THC.
Three main factors determine how long your high will last: 1) How strong the dose of THC is; 2) Whether you inhaled the THC, or took it orally via food, capsules, or drops; and 3) Whether you’re an occasional, regular, or frequent cannabis user.
The typical duration for a high is four hours, with six to seven hours being on the higher end, usually associated with a stronger dose. Very intense doses will produce a high that lasts up to ten hours or more.
It can also be difficult to determine when the high causes impairment while performing tasks such as driving, especially in regular or frequent users. The tolerance that a regular or frequent user builds up enables them to handle many tasks that an infrequent user would not be able to perform, when consuming the same dose.
If you’ve taken too much, and the high is stronger and lasting longer than you bargained for, there are a few things you can do to help ease the effects and help calm you: Taking a nap, or eating black pepper or pine nuts (known for their calming qualities) can be effective.
Consuming CBD, which is also well known for its calming qualities, can help dull the effects of the THC and end the high faster.
Lemon peel can also have the same effect of the CBD, with elements that help dull the THC’s high.
That said, how long a high lasts is very individual, and will depend on the user’s body chemistry and THC tolerance in general.
Source: University of Sydney, Science Alert, Healthline