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Hastings and Prince Edward Public Health
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Cannabis can Affect Your Health

Most people who use cannabis occasionally will not experience negative consequences to their health over time. However, some people will experience harm, especially people under 25 and those who use every day or a few times a week. Not using cannabis is the best way to avoid potential risks to your health.

Cannabis is a plant that has hundreds of chemicals. Some of these chemicals are called cannabinoids, including THC (tetrahydrocannabinol) and CBD (cannabidiol). THC is psychoactive, meaning it affects your brain to create a “high” feeling, while CBD is non-psychoactive.

Cannabis can affect people differently. It can make you feel happy, relaxed and talkative, or it may cause unpleasant effects that can include confusion, sleepiness, anxiety, fear, panic, paranoia, delusions or hallucinations.

Leaves and buds from the cannabis plant can be smoked or vaped. Cannabis can also be used to make oils and waxes that are either smoked, vaped, or consumed by eating or drinking.

Medical Cannabis

Some research shows that the CBD (cannabidiol) found in cannabis may help treat specific medical conditions. Hastings Prince Edward Public Health encourages anyone who is considering the use of cannabis for medical purposes to talk with a health care practitioner and to not self-medicate or access cannabis from the Ontario Cannabis Store for medical purposes.

Know how Cannabis Affects You

There is still a lot to learn about cannabis. Here are a few things to know to help you keep your mind and body safe and healthy:

  • The effects of eating or drinking cannabis take longer to feel and last longer than smoking or vaping. Different strains of cannabis, and the way you use it, can have different effects. The effects of smoking or vaping cannabis can be felt within minutes and can last up to six hours. It can take anywhere from 30 minutes to two hours to feel the effects from eating or drinking cannabis. These effects can last up to 12 hours.
  • Cannabis smoke can be harmful to your lungs. Inhaling any kind of smoke can harm your lungs. Burning cannabis and rolling papers produce smoke that has the same harmful chemicals and carcinogens as the smoke caused by burning cigarettes. These harmful chemicals are made by combustion and are not found in the cannabis plant. Smoking cannabis often can lead to chronic bronchitis, which is a cough that doesn’t go away, lots of mucus and wheezing. Smoking cannabis can also lead to more infections in your lungs, like pneumonia.
  • Cannabis use can lead to dependence. Regular cannabis use can lead to psychological and physical dependence. The risk for dependence is higher for frequent users and people under 25. If you are dependent, you can experience unpleasant feelings called withdrawal symptoms when you reduce how much you use or stop using completely.
  • Cannabis can lead to mental health problems. Using cannabis can increase the risk of experiencing psychosis and schizophrenia, especially if you are a teenager, use everyday or almost everyday, or someone in your family has, or had, these conditions.
  • Cannabis impairs your ability to drive safely. Cannabis impairs the skills everyone needs to drive safely, like judgement, quick response time, attention and coordination. Nobody should use cannabis and drive. For more information visit

Use Responsibly

Using cannabis can come with risks, especially for people who are under 25, use often, or use high levels of THC. These tips can help you make a responsible choice that considers your mental health, physical health, and safety.

Have more cannabis-free days

What to know: Using cannabis every day or a few times a week can increase the risk of negative effects to your mind and body.

How to reduce your risk: Limit your cannabis use to one day a week, at most.

Go easy on your lungs

Ingesting or vaping cannabis is less harmful than smoking, but be aware that these methods may have their own risks.

If you vape, watch for symptoms such as cough, shortness of breath and chest pain. Seek medical attention if you have concerns about your health. Only dried cannabis is legally available for use with a vaporizer.

If you choose to ingest cannabis (e.g. edibles, oils), review the Start low. Go slow. section below for more information.

Obtain cannabis from legal sources. Products from illegal, or unregulated, sources are not subject to any controls for safety or quality.

If you smoke cannabis, avoid inhaling deeply or holding your breath.

Secure your stash.

Keep cannabis products in their original packaging and in a locked place that is out of reach, and out of sight of children or pets.

According to the Canadian Pediatric Society, unintentional ingestion can cause overdose symptoms like severe drowsiness and breathing problems. If this happens, your child needs urgent medical care and may need to be hospitalized. If a child has consumed cannabis, contact the Ontario Poison Control Centre at 1-800-268-9017.

Pace yourself. Start low. Go slow.

What to know:

Different strains of cannabis and the way you use it can have different effects. While you feel the effects of smoking or vaping within minutes, it can take anywhere from 30 minutes to 2 hours to feel the effects of edible cannabis. The effects of edibles can last up to 12 hours.

Synthetic cannabis, like K2 and Spice, are stronger and more dangerous than natural cannabis products. Using these can lead to severe health problems, such as seizures, irregular heartbeat, hallucinations and, in rare cases, death.

How to reduce your risk: Start with a small amount, especially if it is your first time, and wait 30 minutes or more to feel the effects before deciding if you want to have more. Consider using products with low THC and some CBD. You can know how much THC and CBD is in your cannabis by reading the label on the package. If you are sharing with a friend, ask them how much THC is in their cannabis. Don’t use synthetic cannabis products.

Stick to one drug at a time – leave tobacco out of the mix too.

Using more than one drug at a time can lead to unpredictable changes to how you think, feel and act. Tobacco contains nicotine that is also addictive and can make it hard to cut down or quit.

Share with care.

What to know: When you share your joint, bong, vaporizer or whatever else you use, you may also be sharing germs and infections from your mouth and saliva with each other.

How to reduce your risk: Try to avoid sharing with other people.

Plan a safe ride.

What to know: Cannabis impairs the skills everyone needs to drive safely. The effects can last six to 12 hours and could be longer depending on the person and the product used.

How to reduce your risk: If you are planning to use cannabis, plan a safe ride with a sober friend, use public transit, or call a taxi.

Use Legally

Individuals 19 years and older can buy and use cannabis legally. There are restrictions on where you can use, how much you can have in public and grow at home, as well as restrictions on driving after consuming cannabis. See the Frequently Asked Questions section below for more information about the legal use of cannabis in Ontario.

Additional Resources

For Parents

Using cannabis as a teen can change the way the brain grows and how it works. Help your teen reach their full potential: Talk early, often and openly about cannabis.

For Preconception, Pregnancy and Breastfeeding

Cannabis use may affect the ability to become pregnant. There is no known safe amount of cannabis use in pregnancy or when breastfeeding.

Additional Cannabis Education Resources

Getting Help 

Looking for help? You are not alone. There are many programs and resources available to support you.

This page content has been adapted with permission of Ottawa Public Health. For educational and non-commercial purposes only.

Frequently Asked Questions

What is the legal age to buy cannabis?

You must be 19 or older to buy, use, possess and grow non-medical cannabis. This is the same as the minimum age for the sale of tobacco and alcohol in Ontario. It is illegal to share cannabis with anyone who is under 19 years of age.

Where can I buy cannabis?

Individuals 19 years of age and older can buy cannabis at an authorized retailer or through the online Ontario Cannabis Store. Look for the authorized cannabis retail seal to make sure it is a legal store. Legal stores have to get their cannabis from licensed producers. Licensed producers complete testing for quality control and accurate THC levels.

Where can I use cannabis?

Smoking and vaping of cannabis is permitted in some outdoor public places. A complete list of smoke-free and vape-free spaces is available on the Government of Ontario website. Municipalities, landlords, condominium boards and co-operative housing boards may place additional restrictions on cannabis use. Check which rules apply to your residence.

In Hastings and Prince Edward Counties, some municipalities have passed by-laws that restrict smoking of any product at, or near, entrances to municipal buildings, certain transit properties, and municipal parks. As these bylaws are often updated, please contact the Tobacco Talk Line for a current listing of restrictions: or 613-966-5500 ext. 600.

How much cannabis can I have in public?

You can have a maximum of 30 grams (about one ounce) of dried cannabis, or the equivalent in other forms, in public at any time.

Can I grow cannabis at home?

You can grow up to four plants per residence (not per person). Landlords, condominium boards and co-operative housing boards may place restrictions on growing cannabis. Check which rules apply to your residence. Growing at home can cause health and safety risks in your home. If you choose to grow cannabis at home, follow these environmental health and safety tips.

What are the laws about driving after using cannabis?

If you are 21 or under, a novice driver, or a commercial driver, there is a zero-tolerance law for impaired driving, meaning you cannot have any cannabis in your system. To learn more about the laws and penalties for drug impaired driving, visit

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Due to limited supply, HPEPH will initially be prioritizing available bivalent vaccine for residents and workers at identified highest-risk facilities.  Some HPEPH vaccination clinics MAY offer the bivalent vaccine, as availability allows. Vaccine clinics in Hastings and Prince Edward Counties will continue to offer monovalent vaccines (the same mRNA vaccines given as the primary series) for all eligible individuals until a steady supply of the bivalent vaccine is available.

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