Cannabis Health and Safety Information

Cannabis Use Laws in California

It is legal for adults 21 and older to purchase and use recreational cannabis in California, however users should always follow state, county, and local laws.

Safety Tips

It is important if you are using cannabis to follow safety guidelines, specifically if you are storing cannabis products in your home, drinking alcohol, taking other medications, pregnant, breastfeeding, and/or experiencing a health condition. Find more information below on cannabis safety:

The Cannabis Use Disorder Identification Test

Take the test here to measure your cannabis use: English; Spanish 

Services We Offer

The County Health Agency offers a range of services that relate in different ways to cannabis health and safety. This includes:

Please use the links above to contact each of these teams and keep reading for frequently asked questions. If you have questions that aren’t answered here, please contact the Behavioral Health Department or Public Health Department.


For more information regarding the health and safety considerations related to cannabis: 

CDC: Marijuana and Public Health

California Department of Public Health: Let’s Talk Cannabis             

California Department of Public Health: Youth Cannabis Prevention Initiative

Los Angeles, Ventura, Orange and San Bernardino Counties: Marijuana Fact- check

Santa Clara County: Marijuana Is Not for Pregnancy 



Yes. The brain is still developing until the mid-20s. Studies show that using cannabis regularly in your teens and early 20s may lead to physical changes in your brain. Cannabis can harm a young person’s memory and ability to learn and pay attention. Some studies suggest a permanent impact as well. These harmful effects may make it harder for youth to achieve their educational and professional goals, such as graduating high school or attaining a college degree. Cannabis use may also increase the risk for anxiety, depression, suicide and psychotic disorders as well as substance use disorder. For data sources and more information, see Marijuana Fact-check or the California Department of Public Health.

Yes. County Behavioral Health Department staff can provide education and presentations to schools, parents, and community programs. To learn more or arrange for a presentation, contact the County Behavioral Health Prevention & Outreach team at 805-781-4754.

Yes. About one in 10 cannabis users will become addicted. For people who begin using when they are younger than 18, that number rises to one in six. For data source and more information, see CDC’s section on addiction.

Yes, it is possible to use an amount of cannabis that causes problems. A fatal overdose is highly unlikely, but that doesn’t mean cannabis is harmless. The health effects of using too much cannabis are similar to the typical effects of using cannabis but more severe.

This may include:

  • Extreme confusion
  • Anxiety
  • Paranoia
  • Panic
  • Fast heart rate
  • Delusions or hallucinations
  • Increased blood pressure
  • Severe nausea or vomiting

In some cases, these reactions can lead to unintentional injury such as a motor vehicle crash or fall.

Edibles take longer to produce an effect (i.e. up to 2 hours) and overall effects last longer (i.e. up to 12 hours). Therefore, people may consume more to feel the effects faster. This may lead to people consuming very high doses and result in negative effects listed above. For more information, see CDC.

Start Low, Go Slow

  • If it is your first time using an edible, start with a low dose. Take no more than 5mg of THC at one time.
  • Wait at least one hour before consuming more THC.
  • Do not take more than 10mg of THC total.

The County Behavioral Health Department and our community partners offer services that can help you quit using cannabis. Services are available for both youth and adults. To learn more or get started, call 800-838-1381.

No. Using any form of cannabis is not recommended for people who are pregnant or plan to be pregnant soon and people actively breastfeeding.

THC can reach your baby through your bloodstream and into the placenta, breastmilk, and secondhand smoke that enters the baby's lungs.

There is evidence that cannabis can cause issues with your pregnancy and birth and could create long-term problems for your child.

Cannabis effects on newborns can include…

  • Low birth weight or small for gestational age
  • Preterm birth
  • Stillbirth

Cannabis effects on child development can include…

  • Memory
  • Attention
  • Sleep
  • Mood
  • Decision-making
  • Increased hyperactive behavior
  • Increased likelihood of future substance use

If you already use cannabis for medicinal purposes, ask your doctor for an alternative treatment shown to be safe during pregnancy. For data sources and more information, see California Department of Public Health and Santa Clara County’s Marijuana and Pregnancy resources.

While these devices are often considered a safer alternative to smoking cannabis, they are not completely safe or healthy. Experts agree that long-term use of any vaporizing (or e-cigarette) devices may be unhealthy. It is difficult to measure how much THC is inhaled with these devices, especially from high-THC concentrates, so they come with a high risk of using more than you intend to. This is especially true for inexperienced users. It is also likely that people will inhale unknown chemical ingredients when using e-cigarettes or vaping devices. Burns and injuries from exploding e-cigarettes and vaping devices are increasing. For data sources and more information, see Marijuana Fact-check.

Secondhand smoke from burning cannabis has been shown to contain many of the same toxins, irritants and carcinogens as tobacco and wood burning smoke. In fact, results from laboratory testing under standard conditions found that secondhand cannabis smoke contained more than twice as much tar and ammonia as tobacco smoke, and more than eight times as much hydrogen cyanide. California state laws prohibit smoking cannabis in public or in any place where smoking cigarettes is prohibited by law. For data sources and more information, see the CDC.

Cannabis use is still prohibited in public and in areas where smoking tobacco is prohibited. A smoking infraction is punishable with a fine. State and local law currently allows adults 21 years of age and older to use recreational cannabis within a private residence. If you are a renter, your landlord is allowed to prohibit cannabis use within the residence as a part of your lease. Learn more about laws and regulations in SLO County.

Cannabidiol (CBD) is a non-psychoactive cannabinoid that is found in many cannabis products in different amounts. Some products may only contain CBD while others have a combination of THC, the main psychoactive cannabinoid, and CBD. Some short-term effects of CBD can include changes in alertness or mood, drowsiness/sedation, drug interactions that may cause serious side effects, and gastrointestinal distress. Long-term effects of CBD can include liver injury and male reproductive harm. There are still a lot of unknowns about CBD risks and possible benefits that scientists are still researching. Learn more at SAMHSA.

There are limited data and evidence on CBD products’ safety and effectiveness. Over-the-counter CBD products are not FDA-approved and have varying regulation. Some studies have shown that CBD products can often have inaccurate labeling for content and/or potency. The FDA has ruled that CBD products cannot be sold legally as dietary supplements and CBD is not considered a safe additive for food and beverage products. The only currently FDA-approved CBD product is Epidiolex, a CBD oral liquid available by prescription for treating rare, severe forms of seizure disorders. Learn more about FDA regulation of CBD.

Take caution when using CBD products and talk to your doctor first, especially if you have a health condition and/or you are taking other medications that may be impacted by CBD.

Yes, and yes. Cannabis can negatively affect the skills you need to drive safely, including reaction time, coordination, and concentration. If you are under the influence of cannabis while operating a car, boat, or other vehicle, a law enforcement officer can pull you over and conduct a sobriety test. Driving under the influence of cannabis is illegal, just as it is for alcohol and other substances, and increases your risk of getting into a car crash.

To keep yourself and others on the road safe:

  • Make other plans for transportation, such as having a sober friend give you a ride.
  • Take the keys away from a friend who is about to drive while impaired and arrange to get them home safely.
  • Wait at least 6-8 hours to drive after inhaling or consuming cannabis.

Learn more from the CDC.

Cannabis potency has increased in the past decades, up from about 4% in the 1980s to an average of 15% today. Cannabis extracts, used in dabbing and edibles, can contain an average of 50% and up to 90% THC. The main psychoactive, or mind altering, cannabinoid in cannabis is THC. The level of THC in cannabis varies and determines the multitude of effects on the body and the brain. For data source and more information, see Marijuana Fact-check.

Using cannabis can be risky, depending on how you use and what you do afterward. The fact that it’s legal does not mean that it is safe. Using cannabis at an early age can lead to negative health consequences. Other considerations include:

  • Heavy cannabis use (daily or near-daily) can impair memory, learning, and attention, which can last a week or more after the last time someone used.
  • Cannabis use has been linked to anxiety, depression, and psychotic disorders, but scientists don’t yet know whether it directly causes these diseases.
  • Smoking any product, including cannabis, can damage your lungs (i.e. pre-cancerous lesions and chronic bronchitis) and cardiovascular system (i.e. heart disease and stroke).
  • Long-term cannabis use can lead to cannabinoid hyperemesis syndrome, a condition of repeated episodes of nausea and vomiting.

For data source and more information, see the California Department of Public Health.

Store all cannabis products in a locked area that children and pets cannot see or reach. Keep cannabis in the child-resistant packaging from the store and fully reseal after each use. Cannabis affects children more strongly than adults. Children are at higher risk for cannabis poisoning, especially from edibles.

In children, watch for...

  • Loss of coordination
  • Sleepiness
  • Difficulty with breathing

If you think a child may have ingested cannabis, call the Poison Control Center at 1-800-222-1222. If the child collapses, has a seizure, has trouble breathing, or can't be awakened, call 911.

In pets watch for...

  • Stumbling
  • Urinary problems
  • Lack of energy
  • Drooling
  • Vomiting
  • Agitation

If you think your pet may have ingested cannabis, call your veterinarian or the Animal Poison Control Center at 888-426-4435.

Always talk to your healthcare provider about the possible side effects of consuming cannabis while taking prescription medications. Cannabis can dangerously alter the way prescribed medications work, either increasing or decreasing their effects.

Common drugs that are altered when consuming cannabis include:

  • Sedatives (e.g., Ambien, Lunesta and Benadryl)
  • Anti-anxiety medications (e.g., Xanax, Valium and Librium)
  • Antidepressants (e.g., Zoloft, Prozac and Lexapro)
  • Pain medications (e.g., codeine, Percocet and Vicodin)
  • Seizure medications (e.g., Tegretol, Topamax and Depakene)
  • Blood thinners (e.g., Coumadin, Plavix and heparin)

No. Consuming cannabis and alcohol at the same time can be dangerous. Alcohol can increase the body's ability to absorb THC more quickly, creating negative outcomes, including:

  • The "green-out" effect (shivering, chills, sweating, rapid heart rate, lightheadedness, stomach problems, nausea and vomiting, paranoia, anxiety)
  • Alcohol poisoning (i.e., confusion, vomiting, seizures, slow or irregular breathing, pale skin, low body temperature, unconsciousness)
  • Motor vehicle crashes
  • Decreased cognitive function and judgement making skills
  • Other risky behaviors