Within a few minutes of inhaling cannabis smoke, the user will likely feel, along with intoxication, a dry mouth, rapid heartbeat, some loss of coordination and poor sense of balance, and slower reaction time. Blood vessels in the eye expand, so the user's eyes look red.

For some people, cannabis raises blood pressure slightly and can double the normal heart rate. This effect can be greater when other drugs are mixed with cannabis; but users do not always know when that happens.

As the immediate effects fade, usually after 2 to 3 hours, the cannabis user may become sleepy.

The effects of cannabis on each person depend on the

• type of cannabis and how much THC it contains;
• way the cannabis is taken (by smoking or eating);
• experience and expectations of the cannabis user;
• setting where the cannabis is used; and
• use of other drugs and/or alcohol.

Some people feel nothing at all when they first try cannabis. Others may feel high (euphoric).

It's common for cannabis users to become engrossed with ordinary sights, sounds, or tastes, and trivial events may seem extremely interesting or funny. Time seems to pass very slowly, so minutes feel like hours. Sometimes the cannabis causes users to feel thirsty and very hungry-an effect called "the munchies".

Government survey tells:

• cannabis is the most frequently used illegal drug in the United States. Nearly 95 million Americans over the age of 12 have tried cannabis at least once.
• Over 14 million had used the drug in the month before the survey.

The Monitoring the Future Survey, which is conducted yearly, includes students from 8th, 10th, and 12th grades. In 2003, the survey showed that 18 percent of 8th-graders have tried cannabis at least once, and by 10th grade, 17 percent are current cannabis users (that is, used within the past month). Among 12th-graders, 46 percent have tried cannabis / hash at least once, and about 21 percent were current cannabis users.

Other researchers have found that use of cannabis and other drugs usually peaks in the late teens and early twenties, then declines in later years.

Research shows that nearly 50 percent of teenagers try cannabis before they graduate from high school.