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Marijuana Health Information

Cannabis is a drug produced by drying out the flower and other parts of the cannabis plant. Cannabis (often called marijuana, among other names) contains chemicals such as tetrahydrocannabinol (THC) and cannabidiol (CBD). If you need resources or support around cannabis or other substance use, please call 311.

Health effects

Cannabis use affects each person's health in different ways. A person's age, gender, how they use the drug, and other factors, determine how cannabis affects them. Use by young people may cause long-term damage to the brain. Long term use of cannabis may increase the risk of a use disorder, cancer, and other negative effects.

Short term effects can include: 

  • euphoria
  • altered senses
  • changes in mood
  • impaired body movement
  • difficulty with thinking and problem solving
  • decreased/increased anxiety
  • increased appetite
  • rapid heartbeat
  • increased blood pressure
  • red eyes
  • paranoia
  • hallucinations
Ways Cannabis is consumed

Each method of consuming marijuana has its own health and safety risks. 

INHALED: There are different ways to inhale cannabis. You can smoke it in a joint, pipe, or bong. You can also use a vaporizer or vape pen to inhale cannabis. You can also "dab" by heating a cannabis concentrate on a hot surface and inhaling. Smoking cannabis with tobacco products, like blunts and blunt wraps, introduces chemicals known to cause cancer.

EDIBLES: Sometimes marijuana is added to candy, food or drink. You feel the effects of these "marijuana edibles" more slowly, making it easier to overuse.

Download a PDF fact sheet on cannabis health effects in English or Spanish.

Additional Resources

The Centers for Disease Control and Prevention

Massachusetts Department of Public Health

City of Boston - Cannabis Legalization Webpage

Partnership for Drug Free Kids

Teens and Young People

​Cannabis poses unique health risks to young people regardless of how it's used. Cannabis has many different names, including marijuana, weed, pot, and others. It is illegal for a person under the age of 21 to have or use cannabis in any form, unless specified by their doctor.

Cannabis: Teens and Young People

Why do some teens choose to use cannabis? What are some of the health considerations? What are some signs of a potential use disorder? The following fact sheet provides useful information in answering some of these questions. There is also a fact sheet with talking points to foster conversations with young people about cannabis.

Fact Sheets:
  • Cannabis: Teens and Young People Fact Sheet in English and Spanish
  • Cannabis: Talking with Young People about Cannabis Fact Sheet in English and Spanish

For more resources or support around cannabis or other substance use, please call 311.


For more resources or support around cannabis or other substance use, please call 311.

Pregnancy and Breastfeeding

Using cannabis during pregnancy and breastfeeding may present health risks for the baby and the pregnant person.

Health Effects

Any kind of cannabis use while pregnant presents health risks. Risks include fluctuating blood pressure, low birth weight, and negative impacts on children's ability to learn and develop. 

Secondhand Smoke

Marijuana smoke has many of the same harmful chemicals as tobacco smoke. There are still health risks for pregnant people if exposed to secondhand cannabis smoke or vapor.

Morning Sickness

No matter the reason for use, cannabis gets passed to a baby in the womb. Pregnant individuals should talk to their doctor about treating morning sickness.


Chemicals from cannabis pass to babies through breast milk. This may cause poor weight gain, sleepiness, and slower development in infants.

Medical Cannabis

Tell your doctor you are pregnant and need to discuss alternatives to medical cannabis.

Download a Pregnancy and Breastfeeding Fact Sheet in English and Spanish.

Laws to Know

Massachusetts residents voted to legalize cannabis use for medical purposes in 2012. They voted to approve retail sale of cannabis products in 2016.

For more complete information about cannabis laws, visit the Cannabis Control Commission website. Click here to download a Fact Sheet about Cannabis Law.

Buying Cannabis

Licensed dispensaries sell inspected cannabis free of additives, chemicals, molds, and mites. Cannabis inspections also confirm the amount of the active substances in the cannabis products such as THC and CBD. Purchasing cannabis products from anywhere other than a licensed dispensary is illegal. Illegal cannabis products are more likely to contain harmful chemicals, heavy metals, pesticides and other substances.

Cannabis in Public Spaces

The law prohibits smoking or consuming cannabis of any kind in any public place. Public places include public parks, sidewalks, bars, and restaurants. Residents can carry up to one ounce of cannabis in public. Five grams of that ounce may be in the form of cannabis concentrate (such as dabs or wax).

Driving and Cannabis

It is illegal to operate a vehicle under the influence of cannabis. It is also illegal to have open containers of cannabis in a vehicle. You must keep cannabis in a locked glove compartment or trunk. 

Growing Cannabis

Residents 21 years old or older can grow no more than 6 cannabis plants. There can be no more than 12 plants in a household. Plants must be grown in a locked or secured location.

Cannabis in the Home

Many apartment and condominium buildings have smoke-free / vape-free policies that cover cannabis. Some may also have rules prohibiting growing or consuming cannabis on site. Using or growing cannabis in public housing could lead to the loss of housing.

Download a PDF Fact Sheet about Cannabis Law in English or Spanish.

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