CPHI Research Library
The CPHI Public Health Resource Library collects cannabis-related studies and journals to bring awareness to the effects of cannabis on the body. We collaborate with the “It’s up to us” campaign helping San Diegans to talk openly about mental health and to find local resources for support.
Addiction
Cannabis Use Disorder is listed in the DSM-5. Hasin DS. US Epidemiology of Cannabis Use and Associated Problems. Neuropsychopharmacology. 2018;43(1):195-212.
Symptoms of marijuana withdrawal include anxiety, diminished appetite, mood changes, irritability, sleep difficulties, including insomnia, headaches, loss of focus, cravings for marijuana, sweating, including cold sweats, chills, increased feelings of depression, stomach problems. These symptoms can range from mild to more severe, and they vary from person to person. These symptoms may not be severe or dangerous, but they can be unpleasant. The longer someone uses marijuana, the more likely they are to experience withdrawal symptoms.
Impact on mental well-being
Libby Stuyt, MD an addiction psychiatrist in Colorado published an Op-Ed reviewing data from large patient studies within the Veteran’s population, Colorado population, and youth studies.
Han et al., awaiting publication. Dr. Nora Volkow, NIDA slide SAM Summit 2022.
This study compared the incidence of suicide attempts in adults aged 18-45. Cannabis Use Disorder with underlying major depression had the highest incidence of suicide attempts. Cannabis Use Disorder and daily cannabis use increased incidences of suicide attempts both in people with and without major depressive disorder. Females had higher incidences than males in all categories.
This study examined NSDUH (National Surveys on Drug Use and Health) data from 281,650 adults ages 18-34 between January 2008 and December 2019 and noted an increase of 40% to 60% in suicidal ideation, plan and attempt associated with cannabis use and major depression.
This study was conducted utilizing a registry of 13,986 twins from Australia. Amonozygotic (identical) twin who uses cannabis frequently was more likely to report suicidal ideations compared to their identical twin who used cannabis less frequently, even after adjustment for other variants. The study concluded that increased likelihood of suicidal ideation in frequent cannabis users cannot be solely attribute to common predisposing factors.
Impact short- and long-term brain health
Driving
HartmanRL, Huestis MA. Cannabis effects on driving skills. Clin Chem 2013; 59:478-92.
Cannabis is the most prevalent illicit drug identified in impaired drivers. Epidemiological data shows risk of motor vehicle collisions increases by 2-fold after cannabis smoking. Evidence suggests recent smoking and/or blood THC concentrations 2-5 ng/mL areas sociated with substantial driving impairment, particularly in occasional smokers.
Ramaekers JG, Berghaus G, van Laar M, Drummer OH. Dose related risk of motor vehicle crashes after cannabis use. Drug Alcohol Depend. 2004;73:109-19.
Recent smoking of marijuana and blood THC of 2-5 ng per milliliter are associated with substantial driving impairment. According to meta-analysis, the overall risk of involvement in an accident increases by a factor of about two when a person drives soon after using marijuana. In an accident culpability analysis, persons testing at 1 ng/ml of THC or higher were 3-7 times as likely to be responsible for a motor vehicle collision. In comparison, the risk of a vehicular collision increased by almost 5 for a driver with a blood alcohol over 0.08%. The risk of alcohol with marijuana is associated with an increased risk than either drug alone.
191 Participants were given driving simulation test after smoking placebo, 5.9% or 13.4% THC. Increasing willingness to drive at 1 hour 30 minutes may indicate a false sense of driving safety. Worse driving performance is evident for several hours post smoking in many users but appears to resolve by 4 hours 30 minutes in most individuals.
Drug Interactions
Fifty percent of CBD users experienced adverse drug events such as liver failure, sedation, sleep disturbance, infection and anemia. CBD is metabolized in thel iver via the CYP3A4 enzyme and is therefore associated with numerous drug-drug interactions.
THC is metabolized in the liver utilizing the CY3A4 and CYPP2C9 enzymes which results is numerous drug-drug interactions. For example, patients given ketaconazole, afungal treatment medication, had 27% increase in THC and 204% increase in 11-OH-THC (an active metabolite of THC). All participants in the study reported serious adverse effect when THC was combined with ketoconazole. In addition, 35% of Caucasians have genetic alterations in their CYP2C9 enzyme, meaning they cannot metabolize THC as well resulting in higher dosage of THC in their body.
Expecting and New Mothers
The Stillbirth Collaborative Research Network included 59 hospitals in 5 geographic areas between 2006 – 2008. Stillbirth is defined when a fetus dies at or after 20 weeks gestation.
A review of 24 meta-analysis studies demonstrated that women who used cannabis during pregnancy had an increased incidence of anemia. Infant exposed to cannabis in utero had a decrease in birth weight and high likelihood of needing neonatal intensive care services.
In a study of 661,617 women in Ontario Canada, cannabis use during pregnancy was associated with significant association with risk of preterm birth. There was a greater frequency of small for gestational age, placental abruption, transfer to neonatal ICU, and 5-minute APGAR score of less than 4.
This study shows the results of an experiment that shows that long-term, heavy use of cannabis during pregnancy can impair fetal brain development and put the offspring at risk of neurodevelopmental disorders.
Prenatal Cannabis Use and Maternal Pregnancy Outcomes
Findings: In this cohort study of 316 ,722 pregnancies, prenatal cannabis use was associated with increased risk of gestational hypertension, preeclampsia, weight gain greater and less than guidelines, and placental abruption as well as reduced risk of gestational diabetes. No association was found with eclampsia, placenta previa, placenta accreta, or severe maternal morbidity.
Prenatal Cannabis Exposure and Executive Function and Aggressive Behavior at Age 5 Years
Cannabis use during pregnancy is increasingly common in the US and may affect the development and behavior of preschool-aged children.
Results from this contemporary US cohort where prenatal cannabis exposure was common and indicated that exposed children exhibited some differences in aspects of executive function and behavior relevant to long-term academic success and adaptive functioning. These results may be considered in refining clinical recommendations regarding cannabis use during pregnancy.
Physical Health
Page RL, et al. Medical Marijuana, Recreational Cannabis, and Cardiovascular Health: A Scientific Statement From the American HeartAssociation. Circulation. 2020.
Patients with underlying heart disease could experience increase angina when cannabis is smoked.
- Continual cannabis use is associated with increased risk of metabolic syndrome compared to no use.
- The risk of stroke was higher among frequent marijuana users aged 18-44 with concomitant e-cigarette use.
- The public needs high quality information about cannabis, which can help counterbalance the proliferation of rumor and false claims about the health effect of cannabis products.
- There is a need to create knowledge and automated warnings around drug-drug interactions.
- Smoke from marijuana combustion has the same toxins, irritants and carcinogens as tobacco smoke.
- Marijuana smokers have a greater exposer of tar per breath than tobacco smokers.
- Smoking marijuana clearly damages the human lung, and regular use leads to chronic bronchitis and can cause an immune-compromised person to be more susceptible to lung infections.
- No one should be exposed to secondhand marijuana smoke. Secondhand marijuana smoke contains the same toxins and carcinogens found in directly inhaled marijuana smoke, in similar amounts if not more.
- The American Lung Association strongly cautions the public against smoking marijuana as well as tobacco products.
American Lung Association. Marijuana and Lung Health. December 17, 2020. Marit S. Tweet, Antonia Nemanich, Michael Wahl; Pediatric Edible Cannabis Exposures and Acute Toxicity: 2017–2021.Pediatrics February 2023; 151 (2): e2022057761. 10.1542/peds.2022-057761
Cancer risk and legalization of access to cannabis in the USA: overview of the evidence
The cancer type most closely linked to cannabis use is non-seminoma testicular cancer. However, evidence is emerging of an increased risk of other types of cancer (eg, lung squamous cell carcinoma, head and neck squamous cell carcinoma, and oral, breast, liver, cervical, laryngeal, pancreatic, thyroid, and childhood cancer), underscoring the potential importance of incorporating prevention and cessation of cannabis use in cancer prevention efforts.
Youth Edible Exposure
Clarifying the Risks of Consuming Edible Cannabis
A cross-sectional study published in JAMA Internal Medicine found that cannabis legalization in Canada was associated with an increased rate of emergency department visits for edible cannabis poisonings in both older adults and children. Another study at a large urban academic hospital in Colorado found that edible cannabis was more often associated with acute psychiatric and cardiovascular symptoms compared with inhalation exposure.
Unintentional Pediatric Ingestion of Cannabis—Addressing a Growing Public Health Risk
An analysis of the US National Poison Data System data for pediatric exposures to edible cannabis products in children younger than 6 years from 2017 to 2021 concluded, “unintentional cannabis exposures in young children are increasing rapidly,” resulting in hospitalizations and potential toxic reactions. In July 2023, the FDA issued 6 warning letters to companies selling cannabis products intentionally mimicking popular snack food brands. The agency warned that these copycat cannabis products could be easily mistaken for popular foods that are appealing to children. We can, and should, do more to address the public health risks posed by copycat THC products.
Child Protection System Interactions for Children With Positive Urine Screens for Illicit Drugs
In this cross-sectional study of emergency department and inpatient medical encounters, less than half of children with positive urine drug screens were reported to CPS; out-of-home placements were uncommon. With increased encounters for positive drug tests, it is unclear what services these children and families are receiving.
Ingestion of Illicit Substances by Young Children Before and During the COVID-19 Pandemic
In this study of illicit substance ingestions in young children before and during the COVID-19 pandemic, there was an immediate and sustained increase in illicit substance ingestions during the pandemic. Additional studies are needed to contextualize these findings in the setting of pandemic-related stress and to identify interventions to prevent ingestions in face of such stress, such as improved parental mental health and substance treatment services, accessible childcare, and increased substance storage education.
Cannabinoid Hyperemesis Syndrome (CHS)
LaPoint J et al. Cannabinoid Hyperemesis Syndrome: Public Health Implications and a Novel Model Treatment Guidelines. West J Emerg Med. 2018;19(2):380-386. doi: 10.5811/westjem.2017.11.36368.
CHS, cannabis hyperemesis syndrome, occurs in patients with long term inhaled marijuana use who present with painful abdominal pain and wrenching without other identifiable causes.
Cannabinoid Hyperemesis Syndrome (CHS)
Although the exact number of people with CHS is unknown, based on emergency department surveys, CHS is estimated to affect about 2.75 million people in the US yearly. From 2017 to 2021, emergency department visits for CHS doubled in the US and Canada and were most common among males aged 16 to 34 years.
Treatment Guidelines. West J Emerg Med. 2018;19(2):380-386. doi: 10.5811/westjem.2017.11.36368.
CHS, cannabis hyperemesis syndrome, occurs in patients with long term inhaled marijuana use who present with painful abdominal pain and wrenching without other identifiable causes.
NourbakhshM, Miller A, Gofton J, Jones G, Adeagbo B. Cannabis Hyperemesis Syndrome:Reports of Fatal Cases. J Forensic Sci. 2019;64(1):270-274. doi:10.1111/1556-4029.13819.
This is a report of a 27-year-old female and a 27-year-old man whose cause of death was attributed to CHS, cannabis hyperemesis syndrome. A third case of a 31 year old man, CHS was appreciated, but not the cause of death.
Vaping
New study links vaping to increased respiratory symptoms in young adults
Young people who use electronic cigarettes or vape report increased respiratory symptoms, including wheezing and shortness of breath, compared to those who don’t use e-cigarettes, according to a new study.
EVALI or E- Cigarette and Vaping Associated Lung Injury
EVALI stands for e-cigarette or vaping use-associated lung injury. It was originally known as VAPI (vaping associated pulmonary illness). The new name is in response to a growing number of severe lung illness cases related to using e-cigarette and vaping products, the first being identified during 2019. We are still learning about this disease, so changes may continue to be made to the terminology.
E-Cigarettes and Vaping-Related Disease
This study from the CDC compared the characteristics of 60 patients who died from EVALI with those of 2558 patients who were hospitalized for the condition but survived. The deaths were reported from 27 states and the District of Columbia, and most were associated with vaping THC-containing products before symptom onset.
Outbreak of Lung Injury Associated with the Use of E-Cigarette, or Vaping, Products
In August 2019, CDC started collecting data from states on EVALI cases using a standardized case report form. The data were voluntarily collected and submitted by each state to CDC on a routine basis. Due to the subsequent identification of the primary cause of EVALI, and the considerable decline in EVALI cases and deaths since a peak in September 2019, CDC stopped collecting these data from states as of February 2020.
IASIC Medical Library
Always safely store your cannabis products away from children. Cannabis ingestion in children can lead to serious life-threatening illness.
The International Academy on the Science and Impact of Cannabis (IASIC1.org) has an extensive medical library regarding cannabis harms.
Cannabis Public Health Initiative (CPHI)
The San Diego County Cannabis Public Health Initiative (CPHI) works to reduce youth access to cannabis by increasing public awareness regarding the adverse effects resulting from youth cannabis use. Our efforts are aimed at providing the science behind youth cannabis use and its public health impacts.