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A resource to start the conversation
about drug use and abuse.

Marijuana (also known as cannabis, pot, weed, grass,

  • Comes from the Cannabis sativa plant.
  • Looks like a dried herb similar to oregano.
  • Is bought loose or as "buds" in small plastic bags.
  • Is sometimes already rolled into a cigarette called a "joint" or "spliff."
For tips and strategies for talking to your kids about marijuana, take our Talk about Drugs online parent modules.

Hash and hash oil

You might have heard of hash (hashish) and hash oil: 2 substances that also come from the Cannabis sativa plant, but are stronger and more concentrated than marijuana.

Hash is hard and usually black, while hash oil is dark-coloured and sticky like molasses or maple syrup.

How marijuana is used

Marijuana, hash and hash oil are smoked. When smoked they produce a distinct scent that smells different from tobacco smoke. Some people say hash and marijuana smoke smells sweet.

Marijuana can also be eaten as an ingredient in cakes, cookies or other foods. ("Hash brownies" or "pot brownies," for example, are brownies baked with hash or marijuana.)

The chemicals in marijuana

Marijuana contains many of the same chemicals as cigarettes. Tar one of the main chemicals is known to cause lung cancer.


Marijuana has a higher amount of tar than cigarettes. Researchers predict that studies will eventually link marijuana smoke and lung cancer. The way users smoke marijuana by inhaling deeply and holding the smoke in their lungs might also contribute to the damage caused by tar.

THC (tetrahydrocannabinol)
Users smoke marijuana for its THC (tetrahydrocannabinol) the chemical that makes people feel high.

The THC content in marijuana is much higher than it used to be. In the past, marijuana was mostly grown outdoors. Nowadays marijuana is usually grown inside, where growers can carefully control the growing conditions.

One of these controlled growing conditions is the amount of light the cannabis plant is exposed to. The more ultraviolet light a cannabis plant absorbs, the more THC it produces.

Growers have not only increased THC levels, but also changed the chemical balance in marijuana. Researchers are looking into how this different chemical balance might be even more harmful to users.

Effects of marijuana

Marijuana makes most people feel relaxed, laid-back and lazy. Some users become unmotivated and lose interest in doing much of anything. THC (tetrahydrocannabinol), the main chemical in marijuana, affects concentration and makes it difficult to learn.

A person using marijuana might have red or glazed eyes. Many users also get "the munchies": an increase in appetite that makes them want to eat more than usual.

Is marijuana addictive?

Yes, though many kids don't think so.

While users might not get hooked on marijuana as easily as other harmful substances, it's still a common reason why many young people enter drug treatment programs.

Dangers of mixing marijuana and alcohol

When there's too much alcohol in the body, the brain sends a signal to the stomach to vomit. The body gets rid of the excess alcohol by vomiting.


Marijuana lessens the urge to vomit, so a person who smokes marijuana and drinks alcohol at the same time is more likely to get alcohol poisoning.

Mixing marijuana with other drugs

Marijuana can be mixed with other drugs, such as cocaine and crystal meth.

These types of mixtures are much more physically addictive than using only marijuana. Mixing can lead to a person's getting hooked on a particular mixture and having to return to the same dealer. And once a user is hooked on a particular blend, the dealer can raise the price.


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Revised: May 11, 2016


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