Duration is strongly affected by dose, tolerance, and individual reaction. Those who use cannabis regularly experience a shorter duration than those who do not. Note that most cannabis users smoke multiple times in a single session and this extends the duration.For oral consumption, duration is complicated by stomach contents and delivery mechanism. Taking THC-capsules on an empty stomach lasts much shorter than eating THC-containing cookies or food, which take hours to fully digest.There has been some research into the pharmacokinetics of THC (how it moves through and is processed by the body). See Grotenhermen's research , which showed that the peak THC concentration after smoking was between 15-30 minutes and sloped down for 1-2 hours. He also showed that oral consumption caused the THC levels to peak between 2 and 4 hours and last for 4 to 8 hours.

The primary effects sought by those using cannabis recreationally are euphoria, relaxation, and changes in perception. Effects vary depending on dosage, with effects at low doses including a sense of well-being, mild enhancement of senses (smell, taste, hearing), subtle changes in thought and expression, talkativeness, giggling, increased appreciation of music, increased appetite, and mild closed-eye visuals. At higher doses, sense of time is altered, attention span and memory are frequently affected, and thought processes and mental perception may be significantly altered.



One of the most common comments about cannabis is that it enhances the appreciation of sensory experiences without substantially changing the perceptual experience. Many people attribute their love of music, appreciation for new forms of music, and ability to play instruments to the use of cannabis.



At overly high doses, the effects are often likened to other psychedelics and panic and dysphoria (bad mood) are more common. High doses, especially when taken orally, can sometimes result in difficult experiences and trips to the emergency room in response to racing heart, extreme confusion, short-term memory loss, and panic. After high-dose experiences, especially among those who are not regular users, after effects can last 1-2 days.



Paradoxically, although cannabis is normally considered a relaxant / depressant, its effects are stimulating in a substantial portion of those who use it. While some people use it to help them sleep, others cannot sleep for 3-6 hours after their last smoke.



