Understanding Cannabis Dependence

Cannabis sativa is the most commonly used illegal drug in the United States.

The many names of cannabis

Cannabis sativa has many nicknames. More commonly known as marijuana, some of its other popular names include: "grass," "pot," "reefer," "joint," "weed," and "Mary Jane." The plant’s concentrated, resinous form is called "hash", which is short for hashish.

How marijuana is used

People use this plant by smoking its dried leaves, flowers, stems and seeds. But it can also be mixed into food or brewed like tea.

Physiological Effects of Marijuana

Marijuana’s active ingredient delta-9-Tetrahydrocannabinol (THC) is quickly absorbed after smoking a joint. THC and other substances in marijuana smoke cause short-term medical effects in a matter of minutes. Signs of marijuana use include red eyes, dry mouth, increased appetite, ("the munchies"), rapid heart rate, increased blood pressure, increased breathing rate and slow reaction time.

These medical effects decrease after 3-4 hours. But marijuana stays in your system up to 24 hours after smoking. The lingering effects mean you’re impaired for several hours even after the high has worn off.

Psychological effects of marijuana

The main psychological effect  of smoking marijuana is euphoria. People get high or "stoned" when they use this drug. Some of the other psychological effects of marijuana include distorted sense of time, short-term memory loss, magical or random thinking, paranoia, anxiety and depression.

Like the drug’s physiological effects, these psychological signs also ease up after a few hours, but the lingering effects can also last for several hours, even through the following day.

Risk of marijuana use

The risks of smoking marijuana increase with heavy use. The risk of developing the following conditions increases when you use the drug:

  • Lower testosterone levels, sperm count and quality.
  • Decreased libido and fertility (in men).

Marijuana is addictive, at least psychologically. But many experts believe that marijuana is also physically addictive. Even light users or those who use it occasionally (approx. 1 in 12) may feel withdrawal symptoms when they can’t smoke whenever they want. The dependence rates are higher for heavy users.

Some symptoms of withdrawal from marijuana include aggression, anxiety, depression and decreased appetite.

Is marijuana a "gateway" drug?

Experts are still undecided if marijuana is a "gateway" drug, meaning, if it makes people more likely to use "hard" drugs such as cocaine, heroin, ecstasy, etc. Although it’s true that marijuana users are more likely to use other drugs, it is unclear whether smoking marijuana causes further drug use or if people who start smoking marijuana are just generally more likely to try other drugs.

How long does marijuana stay in the system?

How long marijuana stays in the system depends on how heavy your smoke it. Light users often have a negative drug screen after a pot-free week. Heavy users will test positive for about a month after their last use.