Marijuana

Get the facts on what marijuana is and its effects.

Written By: Teens participating in the Summer Wellness Programs

Palo Alto Medical Foundation

Marijuana is often used by teens – but it’s also important to know that not everyone’s using it. In 2017, the Centers for Disease Control and Prevention (CDC) reported that:

36 percent of youth had tried marijuana.
7 percent of youth had tried it before age 13.
20 percent had used it in the past 30 days.

In particular, vaping marijuana has recently increased among teens, according to the National Institute on Drug Abuse (NIDA). In the survey, the number of teens who said they had vaped marijuana in 2019 were:

7 percent of eighth graders.
19 percent of tenth graders
21 percent of twelfth graders.

These numbers are more than double those reported in 2017.

What is Marijuana?

Marijuana refers to the dried, shredded leaves and flowering tops of the Cannabis sativa plant. It’s also called weed, pot, herb and grass. Marijuana can be smoked, swallowed as “greenies,” used to brew tea and mixed in foods (edibles).

There are many varieties of marijuana, both medicinal and recreational. They differ in strength and how they make you feel. Effects can vary by type and how it interacts with your body. Different varieties might make you hungry, anxious, relaxed, sleepy or energetic.

Marijuana use can also:

Cause bloodshot eyes, dry mouth and dry throat.
Cause shaking and rapid heartbeat.
Cause sleep problems.
Distort your perception of time, sounds, sight and touch.
Decrease your motivation and inhibition.
Impair your driving skills, including judgment, coordination and reaction time.
Cause you to see things or feel paranoid.
Harm your schoolwork by dulling your thinking, attention and memory.
Affect your athletic performance by messing up your timing, movement and coordination.
Cause coughing and lung damage similar to that from smoking cigarettes.
Lead to addiction.

Marijuana’s main mind-altering chemical is THC. The amount of THC in marijuana determines its strength and how the drug can affect your body. It affects every person differently, depending on personal body chemistry, the plant’s potency and the ways it’s used or mixed with other drugs, such as alcohol.

CBD products in stores have had the THC removed.

Is Marijuana Safe?

You’re probably aware that some states have legalized marijuana use for adults, so you may think that means marijuana is safe. But just because something is legal doesn’t make it safe. (Take a look at alcohol and cigarettes, both of which are legal for adults – and extremely harmful.) Marijuana’s short- and long-term side effects are real and dangerous.

In all 50 states, it’s illegal for people under age 21 to have, use, grow or sell marijuana, and it’s illegal for anyone of any age to drive under its influence. Even in states where marijuana is legal, companies may still not hire you if you test positive for marijuana use (and marijuana can stay in hair for up to 90 days).

If you’re caught with marijuana, you could:

Lose your driver’s license.
Spend time in court or jail.
Pay huge fines.
Be suspended or expelled from school.
Lose your job or not get hired.

If you’re struggling with marijuana use or worried about a friend, talk to a trusted parent, teacher, doctor or other adult. You can also call the SAMHSA helpline at 800-662-HELP (4357).

What is Medical Marijuana?

Some states have legalized the medical use of marijuana for people suffering from severe and life-threatening health problems. For example, it’s used to increase appetite for people getting chemotherapy, to relieve nausea in people with late-state AIDS and cancer, and to decrease pressure in the eye for people with severe glaucoma.

As far as research can tell, medical marijuana can only relieve symptoms; it doesn’t cure health problems and provides no other health benefits. (There is research underway about its possible impact on epilepsy.)

Resources

Drug Guide from the Partnership for Drug-Free Kids and the Center for Addiction
Marijuana: Facts for Teens
NIDA for Teens
Tips for Teens: Marijuana

Last reviewed: February 2020