Suspected suicide attempts linked to marijuana overdoses have been steadily increasing over the past decade, a new study reports.
National Poison Data System records show a 17% yearly increase in reports of suicidal people who have been poisoned by using too much cannabis, said co-researcher Tracy Klein, an associate professor of nursing at Washington State University College of Nursing, in Vancouver.
Nearly 18,700 cases of suicidal behavior associated with cannabis poisoning were reported to U.S. poison centers between 2009 and 2021, according to the report published online April 19 in JAMA Network Open.
Nearly all cases (96%) involved the use of cannabis along with another substance like alcohol, benzodiazepines or other drugs, the study revealed.
About 10% of these cases resulted in death, major disability, disfigurement or some other tragic outcome, the results showed.
"People could just be misusing multiple substances at the same time and maybe have a preexisting condition like depression or anxiety, where the misuse of those substances really pushes them over the edge,"Klein said. "We are concerned about that because we know that the mental health status of the United States was really compromised during COVID."
These poisonings hit the young and the old particularly hard.
Suicides linked to cannabis poisonings doubled among kids aged 5 to 13 in recent years, rising from 1.3% in 2019 to 3.1% in 2021, the study found.
Meanwhile, seniors aged 65 and older were the age group most likely to die or have a major outcome related to a marijuana-related suicide attempt, Klein said.
Marijuana poisoning involves "using cannabis in the quantity or of the potency to create symptoms distressing enough to require medical attention and/or a phone call to a poison center,"Klein explained.
Edibles have greatly increased the risk of marijuana poisoning, since these products can take 30 minutes to two hours to take effect, the U.S. Centers for Disease Control and Prevention says. People might take a second dose of potent weed when it seems like the first isn't having any effect.
Edibles also cause longer-lasting and unpredictable effects, particularly if they are combined with other substances.
People experiencing marijuana poisoning largely aren't able to fend for themselves, as opposed to folks who have been poisoned in other ways, Klein said.
U.S. poison centers take calls 24 hours a day to provide toxicology expertise in suspected poisoning cases. These calls come in from average people as well as from clinicians at health care facilities.
But health care facilities reported more than 92% of cannabis poisoning cases on record with the National Poison Center in 2021, compared with just 24% for every type of poisoning combined, Klein said.
"That tells me that somebody got sick enough for a medical facility to have to do the reporting for them,"Klein said. "They didn't call themselves."
Still, the new study runs counter to prior research which has found that suicide rates tend to go down in states that legalize medical or recreational marijuana, said Paul Armentano, deputy director of NORML, a group advocating reform of marijuana laws.
"It is well-established that some people suffering from mood disorders self-medicate with cannabis, with varying degrees of success. As a result, some suicidal people consume cannabis, but cannabis consumption doesn't lead one to suicide,"Armentano said.
"As with any disorder, those struggling with depression and other mood disorders are best advised to seek professional care and, if they are consuming too much cannabis, to acknowledge this use with their clinician,"Armentano continued.
But the Partnership to End Addiction said the study suggests that weed use can exacerbate a person's mental problems.
"This study builds upon other research highlighting the relationship between cannabis use, depression and suicidal ideation, which is multifaceted and complex. Cannabis use may worsen preexisting mental health conditions or trigger new ones that can contribute to suicidal ideation,"said Pat Aussem, vice president of consumer clinical content development for the Partnership to End Addiction.
"Cannabis likely provides immediate relief for depressive symptoms, yet typically they worsen over time,"Aussem added. "Also, studies show that people with depression who continue to use cannabis throughout treatment show less improvement on mental health symptoms than individuals with depression who do not use cannabis during treatment."
Klein hopes policymakers will come up with national standards that reduce the risk of cannabis poisoning through requirements for labeling, packaging and serving sizes. She said it's well-known that accidental cannabis poisonings have been increasing since states started legalizing weed.
"Because cannabis isn't really legal as a medicine to be dispensed from a pharmacy, we don't have any consistency from state to state,"Klein said.
States also should reconsider pandemic-era rules that relaxed requirements for cannabis distribution, allowing for home delivery of marijuana products, she added.
In the meantime, anyone with children in their home needs to make sure marijuana products are safely locked away, Klein said.
"Even if a person using cannabis thinks of it as medicine, it might not be packaged like medicine is and might not be labeled like medicine is, and it doesn't come from a pharmacist who talks to you about what's safe and what's not,"Klein said.
"It really puts a lot of responsibility on the person who buys or uses cannabis, with very little guidance, to be informed about the safest, most stringent storage methods that you can use for any cannabis that's anywhere in a household where children could access it,"Klein added.
More information
The U.S. Centers for Disease Control and Prevention has more about marijuana poisoning.
SOURCES: Tracy Klein, PhD, associate professor, nursing, Washington State University College of Nursing, Vancouver; Paul Armentano, deputy director, NORML, Washington, D.C.; Pat Aussem, vice president, consumer clinical content development, Partnership to End Addiction; JAMA Network Open, April 19, 2023, online