blue static


A Note About Cannabis/Marijuana:

The legal status of cannabis in the state of Virginia has recently changed. Student Health and Wellness (SHW) continues to provide evidence-based care focused on student safety and well-being. We recognize the ongoing research as it relates to cannabis and its pharmacologic components. Our aim is to help you optimize your well-being and health, and to respect your autonomy while providing confidential care and support. We encourage you to reach out if you have questions and/or want to discuss your substance use.  

  • Although medicinal cannabis became legal for Virginians in 2017, the staff at SHW do not certify or prescribe it. Patients seeking this treatment outside of SHW must meet certain criteria and must be issued a certification by a registered practitioner. SHW staff do not issue such certifications.  
  • For more information about our free and confidential substance use services, please email Sean Sembrowich, NP.
  • If you have an urgent need, or are in crisis and need to talk to someone immediately, please call SHW (during office hours: 434-924-5362; after hours: 434-297-4261) and let them know you have a medical concern or wish to speak with a mental health provider. For life-threatening emergencies, please call 911.

Learn more about cannabis

Cannabis FAQs

What is cannabis?

Cannabis is the dried flowers and leaves from the cannabis plant.  It contains varying levels of delta-9-tetrahydrocannabinol (THC), the component responsible for euphoria and intoxication, and cannabidiol (CBD), among other cannabinoids. While CBD is not intoxicating and does not lead to addiction, its long-term effects are largely unknown, and most CBD products are untested and of uncertain purity.3

There are many forms of cannabis, and each one can affect an individual differently.  Cannabis can be smoked in a joint or using a pipe or bong.  It can be vaped.  It can be mixed in food, candy, etc. or brewed as a tea (edibles).  Another form is dabbing – the concentrated oil is heated and the vapor is inhaled.  Dabbing is extremely potent.  Topical products (lotions, salves, and balms) often have a higher CBD content than THC.  Aside from Epidiolex (seizure treatment), there are no other FDA-approved drug products that contain CBD.

The amount of THC in cannabis (potency) has increased significantly over the past few decades.  In the early 1990s, the average THC content in cannabis was less than 4%.  It is now approximately 15% and can be much higher (23-90%) in products known as dabs or waxes. 27, 5, 6

When cannabis is smoked or vaped, effects are almost immediately noticeable and last from 1-3.5 hours. 33, 30 Cannabis consumed in food or drink (edibles) have a delayed initial effect of 30 minutes to two hours, as it has to pass through the digestive system.  The effects from edibles may last for 5-8 hours or longer.30  Detectable amounts of THC may remain in the body for days (after occasional use) or even weeks (after more chronic use).38

How common is cannabis use among students?

The March 2021 UVA Spring Health Survey reported that 15% of UVA undergraduate students have used cannabis in the past 30 days (n=607).  62% of UVA undergraduates reported never using cannabis.18

What's the difference between the terms "cannabis" and "marijuana"?

While some places use the terms “cannabis” and “marijuana” interchangeably, SHW uses the term “cannabis.”  This is a deliberate choice, due to the historical context and social impact of the phrase “marijuana.”  Though marijuana is the most common name for cannabis in the U.S. today, its history is deeply rooted in racism and politics.

There is a longstanding theory that narcotics agents in the 1930s chose “marijuana,” a word of Mexican-Spanish origin, over the more scientific “cannabis” when crafting drug laws in order to play into the U.S.’s growing fear of immigrants.  “Marijuana” was also connected with Black jazz musicians in an attempt to racialize its use after the end of prohibition.  

Furthermore, in Virginia, a 2020 report found that Black Virginians were disproportionately policed and convicted for using cannabis, even after law shifts had already begun to occur.2

What does Virginia law say about cannabis (and what does this mean, on and off Grounds)?

Legal ramifications, like health effects, can play a role in informed decision-making.

It is legal:

  • For adults 21 years and older to possess up to one ounce of cannabis for personal use.
  • For adults 21 years and older to grow up to four plants per household (not per person) under certain conditions.
  • For adults 21 years and older to “gift” up to one ounce to another adult of legal age.

It remains illegal:

  • For anyone to possess more than one ounce of cannabis.
  • For anyone to purchase cannabis.  It can only be grown for personal use or gifted to another person of legal age.
  • For anyone under the age of 21 to consume, purchase, or possess cannabis.
  • To distribute or sell cannabis, and/or to possess any amount with the intent to distribute or sell it.
  • To use cannabis while driving or riding in a motor vehicle.
  • To possess cannabis (including medicinal cannabis) on school grounds (including any University property or UVA-affiliated programs/activities off Grounds).
  • To use or offer cannabis to another person in any public space (on or off Grounds).


Learn more about the University’s alcohol and drug policy.
Learn more about Virginia law.

What are the health effects?

Like all substances, there are many factors that combine to determine what kind of effect(s) cannabis will have on an individual – for instance, the potency of THC, frequency of use, the individual’s tolerance level, the age of first use, route of use, family history (genetics), and whether other substances are used at the same time.  

Learn More About Cannabis

Potential Benefits

Most of the cannabinoid receptors are found in parts of the brain that influence pleasure, memory, thinking, concentration, sensory and time perception, and coordinated movement.27 The absorption of THC causes the “high,” stimulating the release of dopamine in the brain’s reward centers27 and allowing an individual to potentially experience a pleasant euphoria and sense of relaxation.38  Other effects, which may vary dramatically among different people, include heightened sensory perception (e.g. brighter colors), laughter, altered perception of time, and increased appetite.38

Beyond the “high” that some individuals experience, cannabinoids have demonstrated the potential for a wide potential spectrum of therapeutic uses.  For instance, it is used in the treatment of chemotherapy-induced nausea and vomiting, and appetite and weight loss related to HIV/AIDS.41 A THC/CBD medication is used for the muscle spasticity in Multiple Sclerosis.42 There is a FDA-approved CBD medication to treat certain pediatric seizure disorders.40 There is also substantial evidence that cannabinoids are effective for chronic pain.36  Early evidence exists for additional potential therapeutic benefits, however, more research needs to be done before definitive conclusions can be made.36

Additional Short-Term Potential Harms to Consider

  • Impaired Driving – Cannabis affects a number of skills required for safe driving – alertness, concentration, coordination, and reaction time.  Cannabis makes it hard to judge distances and react to signals and sounds on the road.27, 39  This significantly increases the risk of a motor vehicle crash.20, 21, 29, 30 And combining cannabis with alcohol, even a small amount, increases the risk further, more than either substance alone.27, 32 It’s not safe to drive high or ride with someone under the influence.
  • Unintentional overdose – Edible cannabis takes more time to absorb and to produce its effects, which increases the risk of an unintentional overdose.  Some may think the initial “dose” is not enough, and consume more and more waiting for the “high.” The body gets overwhelmed with THC, which can lead to uncomfortable symptoms and an emergency room visit.27, 30, 33

Potential Harms

Because THC potency can vary among different strains and even from different plants within the same strain, as well as could be “cut” with other substances, true product content can be largely unknown.  If content is unknown, side effects can also be unpredictable.

Also, pleasant experiences with cannabis are not universal.  Instead of euphoria and relaxation, some people experience anxiety, fear, distrust, or panic.38 These effects are more common when a person takes too much, the cannabis has a high potency, or the person is inexperienced with cannabis use.38  Additional short-term effects can include change in mood, lack of coordination, slow reaction time, difficulty with thinking and problem-solving, disrupted learning and memory (for days or even weeks),28 increased heart rate, hallucinations, and/or delusions.27

Additional Long-Term Potential Harms to Consider

  • Respiratory Effects – People who smoke or vape daily or near-daily may have a daily cough, bronchitis, mucus, and wheezing.  Secondhand smoke/vapor also has many of the same cancer-causing chemicals as secondhand smoke from tobacco.2
  • Mental Health – Research has identified links between cannabis use and mental health issues.  While additional data is needed, some evidence links chronic cannabis use with depression, anxiety and suicidal behaviors.10, 19, 39 The risk for schizophrenia, psychosis, and psychotic disorders increases with frequency of use, THC potency, family history, and as the age at first use decreases.8, 17, 19, 21, 30
  • Addiction – Approximately 1 in 10 people who use cannabis may develop what is called a cannabis use disorder – difficulty quitting or cutting down, continuing to use despite negative consequences, using in larger amounts or for longer than intended or desired, giving up important activities in favor of cannabis use, increased tolerance, etc.  When they start before age 18, the rate of addiction rises to 1 in 6.31, 39  Higher THC potency and increased frequency of use also increase the risk of developing a cannabis use disorder.4, 9
  • Another indicator of a cannabis use disorder is the presence of withdrawal when cannabis use is stopped.  These symptoms may include irritability, disturbed sleep, lack of appetite, anxiety, depression, and cannabis cravings.  These effects can last for several days to a few weeks after cannabis use is stopped.  Returning to cannabis use after cessation is common during this period because people may crave cannabis to relieve these symptoms.27
There is an increased risk of negative effects for individuals who...
  • Are pregnant or breastfeeding – No amount of cannabis use during pregnancy is known to be safe.12  Regular cannabis use during pregnancy has been linked to low birth weight and has also been shown to affect children’s cognitive functioning, behavior and mental health.20, 30, 39  In 2018, the American Academy of Pediatrics recommended that cannabis should not be used during pregnancy.22

    • Maternal cannabis use may still be dangerous to the baby after birth. THC has been found in breast milk for up to six days after the last recorded use. It may affect the newborn’s brain development and result in hyperactivity, poor cognitive function, and other long-term consequences.23, 24, 25, 39 Additionally, cannabis smoke contains many of the same harmful components as tobacco smoke.26

  • Have a family history of psychosis or addiction – Chronic cannabis use and the early initiation of cannabis use are associated with an increased risk for schizophrenia, psychosis and psychotic symptoms.21, 19, 30, 8 The relationship between cannabis use and psychosis is much more likely in people with a pre-existing genetic risk or a personal or family history of psychotic symptoms.19, 21  Genetics and family history of substance use disorders can also increase the risk of someone developing a cannabis use disorder.

  • Are younger than ~25 – The human brain continues to develop from before birth into the mid-20s and is vulnerable to the effects of addictive substances.13  Frequent cannabis use during adolescence/young adulthood is associated with:

    • Changes in attention, memory, decision-making, and motivation – Deficits have been detected even after a month of abstinence10, 14, 19, 21

    • Impaired learning – Declines in IQ, school performance that jeopardizes professional and social achievements, and life satisfaction15

    • Increased rates of school absence and drop-out, as well as suicide attempts16

    • Risk for and early onset of psychotic disorders, such as schizophrenia17

    • No amount of cannabis use during adolescence/young adulthood is known to be safe.12

  • Use high potency cannabis – Exposure to higher concentrations of THC increases the risk of:

    • Addiction7

    • Anxiety, agitation, paranoia, and cannabis-induced psychosis2, 8, 34, 35

    • Hallucinations (not knowing what is real)

    • Cannabinoid hyperemesis – A condition which is marked by severe cycles of nausea and vomiting, sometimes requiring a visit to the emergency room (This mainly occurs with chronic use of high potency THC)11

  • Combine cannabis with other drugs – Using alcohol and cannabis at the same time is likely to result in greater impairment than when using either one alone.  Using cannabis and tobacco at the same time may lead to increased exposure to harmful chemicals, causing greater risks to the lungs and the cardiovascular system.  Cannabis may also change how prescription drugs work.  Always talk with your doctor about any medications you are taking or thinking about taking and possible side effects when mixed with other things like cannabis.37



3. Bonn-Miller M.O., Loflin M.I.E., Thomas B.F, et al. Labeling Accuracy of Cannabidiol Extracts Sold Online. JAMA. 2017;318(17):1708-1709. Doi:10.1001/jama.2017.11909.

4. Crépault, J.-F. (2014). Cannabis policy framework. Retrieved from the Centre for Addiction and Mental Health website: yframework.pdf

5. Elsohly, M.A., Mehmedic, Z., Foster, S. (2016). Changes in Cannabis Potency Over the Last 2 Decades (1995-2014): Analysis of Current Data in the United States. Biological Psychiatry, 79(7), 613-619. Doi:10.1016/j.biopsych.2016.01.004.

6. Azghari, S.K., Fung, V., Rickner, S.S., Chacko, L., & Fleming, S.W. (2017). To Dab or Not to Dab: Rising Concerns Regarding the Toxicity of Cannabis Concentrates. Cureus, 9(9), e1676. Doi:10.7759/cureus.1676. 

7. Freeman, T. P., & Winstock, A. R. (2015). Examining the profile of high-potency cannabis and its association with severity of cannabis dependence. Psychological medicine, 45(15), 3181–3189. doi:10.1017/S0033291715001178

8. Volkow N.D., Baler R.D., Compton W.M., Weiss S.R.B. Adverse Health Effects of Cannabis Use N Engl J Med. 2014 June 5; 370(23): 2219–2227. doi:10.1056/NEJMra1402309.

9. Genen, L. (2017). Clinical presentation of cannabis-related disorders. Retrieved from

10. George, T., & Vaccarino, F. (Eds.). (2015). Substance abuse in Canada: The effects of cannabis use during adolescence. Retrieved from the Canadian Centre on Substance Use and Addiction website:

11. Galli, J.A., Sawaya, R.A., Friedenberg, F.K. Cannabinoid Hyperemesis Syndrome. Curr Drug Abuse Rev. 2011 Dec; 4(4): 241–249.


13. Levine, A., Clemenza, K., Rynn, M., & Lieberman, J. (2017). Evidence for the Risks and Consequences of Adolescent Cannabis Exposure. Journal of the American Academy of Child & Adolescent Psychiatry, 56(3), 214-225. Doi:10.1016/j.jaac.2016.12.014.

14. Meruelo AD, Castro N, Cota CI, Tapert SF. Cannabis and alcohol use, and the developing brain. Behav Brain Res. 2017;325(Pt A):44–50. doi:10.1016/j.bbr.2017.02.025.

15. Meier M.H., Caspi A., Ambler A., et. al. Persistent cannabis users show neuropsychological decline from childhood to midlife. Proc Natl Acad Sci USA., 2012. Oct 2; 109(40) E2657-64 doi 10.1073/pnas. 1206820109. Epub 2012 Aug 27

16. Sillins, E., Horwood, L. J., & Patton, G. C. (2014). Young adult sequelae of adolescent cannabis use: An integrative analysis. The Lancet Psychiatry, 1(4), 286-293. doi:10.1016/s2215-0366(14)70307-4.

17. Di Forti, M., Quattrone, D., & Freeman, T. (2019). The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): A multicenter case-control study. The Lancet Psychiatry, 6(5), 427-436. doi:10.1016/S2215-0366(19)30048-3.

18. March 2021 UVA Spring Health Survey

19. McInnis, O. A., & Porath-Waller, A. (2016). Clearing the smoke on cannabis: Chronic use and cognitive functioning and mental health — An update. Retrieved from the Canadian Centre for Substance Use and Addiction website:

20. Beirness, D. J., & Porath-Waller, A. J. (2015). Clearing the smoke on cannabis: Cannabis use and driving — An update. Retrieved from the Canadian Centre on Substance Use and Addiction website:

21. Fischer, B., Jeffries, V., Hall, W., Room, R., Goldner, E., & Rehm, J. (2011). Lower risk cannabis use guidelines for Canada (LRCUG): A narrative review of evidence and recommendations. Canadian Journal of Public Health, 102, 324-327.

22. Ryan et al: Cannabis use during pregnancy and breastfeeding: implications for neonatal and childhood outcomes. Pediatrics. 2018; 142(3):,e20181889.

23. Bertrand, K. A., Hanan, N. J., Honerkamp-Smith, G., Best, B. M., & Chambers, C. D. (2018). Cannabis Use by Breastfeeding Mothers and Cannabinoid Concentrations in Breast Milk. Pediatrics, 142(3). doi:10.1542/peds.2018-1076.

24. Metz TD, Stickrath EH: Cannabis use in pregnancy and lactation: a review of the evidence. Am J Obstet Gynecol. 2015;213(6):761-778.

25. Effects while pregnant or breastfeeding. (2017, March 02). Retrieved from

26. Moir, D., et al., A comparison of mainstream and sidestream cannabis and tobacco cigarette smoke produced under two machine smoking conditions. Chem Res Toxicol 21: 494-502. (2008).


28. Crean RD, Crane NA, Mason BJ. An evidence based review of acute and long-term effects of cannabis use on executive cognitive functions. Journal of Addiction Medicine 2011;5:1-8.

29. McKiernan, A., & Fleming, K. (2017). Canadian youth perceptions on cannabis. Retrieved from the Canadian Centre for Substance Use and Addiction website: en.pdf

30. National Academies of Sciences, Engineering, and Medicine. (2017). The health effects of cannabis and cannabinoids: The current state of evidence and recommendations for research. Retrieved from

31. Winters KC, Lee C-YS. Likelihood of developing an alcohol and cannabis use disorder during youth: association with recent use and age. Drug Alcohol Depend. 2008;92(1-3):239-247. doi:10.1016/j.drugalcdep.2007.08.005.

32. Hall, W. (2015). What has research over the past two decades revealed about the adverse health effects of recreational cannabis use? Addiction, 110, 19-35. doi:10.1111/add.12703

33. MacCoun, R. J. & Mello, M. M. (2015). Half baked — The retail promotion of cannabis edibles. New England Journal of Medicine, 372, 989-991. doi:10.1056/NEJMp1416014



36. National Academies of Sciences, Engineering and M. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Natl Acad Press. 2017. doi:10.17226/24625.




40. Devinsky O, Cross JH, Laux L, et al. Trial of Cannabidiol for Drug-Resistant Seizures in the Dravet Syndrome. N Engl J Med. 2017;376(21):2011-2020.doi:10.1056/NEJMoa1611618.

41. NIH Drug Database: Dronabinol (Marinol, Synthetic THC). 3.

42. Pharmaceuticlas G. Sativex (delta-9- tetrahydrocannabinol and cannabidiol). delta-9-tetrahydrocannabinol-and- cannabidiol.