Implications of Marijuana Legalization and Identification of THC Toxidrome in the Young

Column Author: Sarah Gwazdacz, MD | Pediatric Resident

Column Editor: Angela D. Etzenhouser, MD, FAAP |Associate Director, Pediatric Residency Program, Assistant Professor of Pediatrics, University of Missouri-Kansas City School of Medicine; Clinical Assistant Professor of Pediatrics, University of Kansas School of Medicine

Recreational marijuana first became legal in two states in 2012. As of January 2023, only four states have not decriminalized marijuana in some capacity.¹ A challenge to legalizing marijuana is a decrease in perceived harmfulness² despite the fact that it remains a Schedule 1 federal substance. Between 2017 and 2021, marijuana exposures in children less than 6 years of age increased 1375%.³ Edible forms of tetrahydrocannabinol (THC) are the most common source in the pediatric population as they are manufactured to look like common snacks.⁴ Therefore, children may accidentally consume products that could contain 10-20 times the typical oral dose of THC for adults.⁵

Marijuana ingestion most often presents with central nervous system symptoms (e.g., hypotonia, somnolence, ataxia, agitation, dysphoria); however, cardiovascular, gastrointestinal, ocular and respiratory symptoms can also be present.³ Severe toxicity can result in hypotension requiring vasopressors, respiratory failure requiring intubation, seizures or coma. Symptoms typically begin one to two hours after ingestion, with severe symptoms typically becoming apparent within four hours of ingestion.¹ The marijuana toxidrome has nonspecific symptoms and mimics other serious conditions; therefore, unnecessary tests are often performed with high associated hospital costs.⁶ Typically, labs will be normal, but cannabinoid toxicity may result in elevated lactate and leukocytosis, although this finding is neither specific nor sensitive.⁷ Detecting marijuana can be difficult as plasma concentrations begin to decline prior to the time of peak effects.⁸ Therefore, screening is done by detecting inactive metabolites in the urine.

Management of intoxication is supportive and most often no intervention is required. In mild cases, symptoms typically resolve within six hours and resolve within 24 hours in prolonged or severe cases.^1,3 Death due to cannabis overdose has not been reported in the literature. However, evidence shows that the pediatric population experiences more overdose-related morbidity than does the adult population.⁹ Triaging the patient depends on obtaining a reliable history on the amount of marijuana consumed and when the ingestion occurred. Pepin et al. performed a retrospective review of children aged < 6 with edible cannabis ingestions and concluded that patients who consumed more than 1.7 mg/kg should be managed in the inpatient setting due to risk of prolonged (more than six hours) return to baseline and severe symptoms.¹ Relying on dose alone is challenging as the amount consumed may be unknown, and the dose may be unreliable if obtained from an unregulated market. Therefore, Pepin et al. also concluded that asymptomatic children two hours after ingestion and patients who do not have severe symptoms four hours after ingestion are safe to discharge.¹

With the growing availability of cannabis, preventive counseling from pediatricians is necessary. Multiple studies have shown that the most common source of marijuana exposure is in the home, and children aged 2-3 are most often affected by accidental exposure.^3,6 The American Academy of Pediatrics (AAP) has released a statement encouraging people under the age of 21 to avoid cannabis use in any form. They also recommend parents and caregivers avoid cannabis use in front of children. The AAP statement goes on to recommend storing all cannabis products in a locked location out of reach of children along with a recommendation that cannabis products should be sold in child-proof packaging.¹⁰ Few states have passed regulations requiring child-resistant packaging; however, it is important to remember that packaging is not a substitute for proper safe storage.⁴ Safe storage is particularly important given that the ability to appropriately supervise children may be diminished when caregivers are under the influence themselves.¹¹

Parents should be educated on the importance of contacting poison control if their child ingests cannabis and to look on the container to estimate the dose consumed. All cases of cannabis ingestion should be reported to local poison control for epidemiologic tracking and future regulation on these products. There is currently no consensus on the need to report to authorities given the substance’s legalization, but reporting is worth consideration given our role to protect a child at risk. A child who has had one poisoning is at risk for a second occurrence.¹² Contacting social work or child protective services may provide families with additional education on storage or resources to decrease the use of parental marijuana use. For recommendations from the AAP on how to talk to parents about keeping their kids safe from cannabis, visit https://www.healthychildren.org/English/ages-stages/teen/substance-abuse/Pages/Edible-Marijuana-Dangers.aspx#:~:text=Teach%20your%20kids%20to%20ask,particular%20risks%20of%20marijuana%20edibles.

References:

1. Pepin LC, Simon MW, Banerji S, Leonard J, Hoyte CO, Wang GS. Toxic tetrahydrocannabinol (THC) dose in pediatric cannabis edible ingestions. Pediatrics. 2023;152(3):e2023061374. doi:10.1542/peds.2023-061374\
2. Ladegard K, Thurstone C, Rylander M. Marijuana legalization and youth. Pediatrics. 2020;145 (Suppl 2):S165-S174. doi:10.1542/PEDS.2019-2056D
3. Tweet MS, Nemanich A, Wahl M. Pediatric edible cannabis exposures and acute toxicity: 2017–2021. Pediatrics. 2023;151(2): doi:10.1542/peds.2022-057761
4. Wang GS, le Lait MC, Deakyne SJ, Bronstein AC, Bajaj L, Roosevelt G. Unintentional pediatric exposures to marijuana in Colorado, 2009-2015. JAMA Pediatr. 2016;170(9):e160971. doi:1001/jamapediatrics.2016.0971
5. Blohm E, Sell P, Neaavyn M. Cannabinoid toxicity in pediatrics. Curr Opin Pediatr. 2019;31(2):256-261.
6. Bashquoy F, Heizer JW, Reiter PD, Wang GS, Borgelt LM. Increased testing and health care costs for pediatric cannabis exposures. Pediatr Emerg Care. 2021;37(12):e850-e854.
7. Vo KT, Horng H, Li K, et al. Cannabis intoxication case series: the dangers of edibles containing tetrahydrocannabinol. Ann Emerg Med. 2018;71(3):306-313. doi:10.1016/j.annemergmed.2017.09.008
8. Huestis MA. Human cannabinoid pharmacokinetics. Chem Biodivers. 2007;4(8):1770-1804. doi:10.1002/cbdv.200790152
9. Klimkiewicz A, Jasinska A. The health effects of cannabis and cannabinoids. Psychiatria. 2018;15(2);88-92. doi:10.17226/24625
10. Ladegard K, Thurstone C, Rylander M. Marijuana legalization and youth. Pediatrics. 2020;145(Suppl 2):S165-S174. doi:10.1542/PEDS.2019-2056D
11. Osterhoudt K., Longo L. Rise in child injury from cannabis: not the high we wanted. Research in Action blog. March 1, 2022. https://Injury.Research.Chop.Edu/Blog/Posts/Rise-Child-Injury-Cannabis-Not-High-We-Wanted
12. Demorest RA, Posner JC, Osterhoudt KC, Henretig FM. Poisoning prevention education during emergency department visits for childhood poisoning. Pediatr Emerg Care. 2004;20(5):281-284.