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According to the Office of National Drug Control Policy, over the last two decades marijuana has become increasingly more powerful, most significantly in states where it has been legalized for recreational use. Click to learn more.

What Is Marijuana?

Marijuana is the dried flowers, leaves and stems of the Cannabis sativa plant. The main active ingredient in marijuana is THC (delta 9 tetrahydrocannabinol). Marijuana can range from 1% THC to 8%. Hashish can be 7% to 14% THC and hash oil is up to 50% THC. THC is a fat soluble substance and can remain in the lungs and brain tissue for up to 3 weeks. Marijuana also contains CBD, which does not produce a high feeling and some people use it for medical reasons. There are over 200 nicknames for marijuana, including pot, herb, mary jane and chronic.

What Are The Forms of Marijuana?

There are a variety of ways to use cannabis and each one can affect people differently.

  • Smoking. Cannabis can be smoked in a joint or using a pipe or bong. This is how most people use cannabis.
  • Vaping. Vaporizers heat cannabis to release THC (the psychoactive ingredient in cannabis) and the vapor is inhaled. This method is growing in popularity.
  • Dabbing/hash oil. THC extract from cannabis, also called shatter, rosin, or concentrates, can contain up to 60-80% THC and may take effect very quickly. When dabbing, the oil is heated and the vapor is inhaled. Dabbing is extremely potent.
  • Edibles. Edibles are food, snacks, or candies that are cooked with cannabis products and contain THC. The effects of edibles, teas and sodas can take longer to peak and last longer than smoking. This can delay the onset of feeling high and can cause people to take too much. It can take up to four hours to feel the full effects, and effects can last up to ten hours or longer. In commercially-available edibles, a standard serving size is 10 mg of THC. It is difficult to know how much THC is in homemade edibles.
  • Topicals. These products often have a higher CBD content than THC. They include infused lotions, salves and balms and are sold for localized pain and inflammation related to skin problems or pain. Due to the higher CBD content and topical application, they do not make the user feel high.

Why Do People Use Marijuana?

Marijuana can relax a person and elevate their mood. This can be followed by drowsiness and sedation. Other effects include heightened sensory awareness, euphoria, altered perceptions and feeling hungry (“the munchies”). High concentrations of THC may produce a more hallucinogenic response.

What Are The Short Term Dangers?

Discomforts associated with smoking marijuana include dry mouth, dry eyes, increased heart rate and visible signs of intoxication such as bloodshot eyes and puffy eyelids. Other problems include:

  • Impaired short-term memory
  • Difficulty thinking and problem solving
  • Anxiety attacks or feelings of paranoia
  • Impaired muscle coordination and judgment
  • Increased susceptibility to infections
  • Dangerous impairment of driving skills. Studies show that it impairs braking time, attention to traffic signals and other driving behaviors. This impairment can last 12 to 24 hours due to accumulation of marijuana in fatty tissue.
  • Cardiac problems for people with heart disease or high blood pressure, because marijuana increases the heart rate

What Are The Long Term Dangers?

Memory and learning
Research shows that regular marijuana use compromises the ability to learn and to remember information by impairing the ability to focus, sustain, and shift attention. One study also found that long-term use reduces the ability to organize and integrate complex information.

In addition, marijuana impairs short-term memory and decreases motivation to accomplish tasks, even after the high is over. In one study, even small doses impaired the ability to recall words from a list seen 20 minutes earlier.

Mental Illness
Marijuana use is associated with increased prevalence of depression, schizophrenia and psychosis. It remains unclear whether marijuana triggers the onset of these illnesses only in vulnerable people or whether it can cause them in people who would not have developed them otherwise.

Long-term marijuana use suppresses the production of hormones that help regulate the reproductive system. For men, this can cause decreased sperm counts and sperm motility and heavy users can experience erectile dysfunction. Women may experience irregular periods from heavy marijuana use. These problems would most likely result in a decreased ability to conceive but not lead to complete infertility.

How To Recognize A Problem

Some warning signs are:

  • More frequent use
  • Needing more and more to get the same effect
  • Spending time thinking about using marijuana
  • Spending more money than you have on it
  • Missing class or failing to finish assignments because of marijuana
  • Making new friends who do it and neglecting old friends who don’t
  • Finding it’s hard to be happy without it

Because THC is fat soluble and remains in the body for up to 3 weeks, it’s important to remember that withdrawal symptoms might not be felt immediately. If you find that you can’t stop using marijuana, then remember, there’s help on campus.


Informational Articles and Links:

How Dangerous is Marijuana, Really?

Science Daily: Marijuana News

Live Science: Marijuana Articles and News

Is Marijuana as Safe as We Think?

Edibles are tied to more severe health issues than smoking marijuana

Drug Fact Sheet: Marijuana