What to know about the deadly cannabis hyperemesis syndrome
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Chronic cannabis users suffering from cannabis hyperemesis syndrome can now be formally diagnosed.
Why it matters: The World Health Organization's recent move to formally name the condition — which includes symptoms such as nausea and vomiting — gives doctors the chance to track prevalence and get a better picture of adverse events.
- Physicians have struggled to differentiate the condition from medical issues like food poisoning or stomach flu, unless they were told the patient was a longtime cannabis user.
- Hospital visits for the condition have remained steady and elevated since the pandemic, raising the call for more awareness to the syndrome.
State of play: In October, the World Health Organization formally added an official diagnosis code for cannabis hyperemesis syndrome to its manual.
- The guidance from the WHO is followed by the Centers for Disease Control and Prevention, giving American physicians the opportunity to diagnose people with the condition, too.
- On Nov. 18, researchers at the University of Washington praised the change as it allows them to recognize trends among patients for the syndrome.
- The change comes as a new study published by the Journal of the American Medical Association (JAMA) on Nov. 24 found that hospital visits for the syndrome rose during the pandemic and have "remained elevated."
Here's what to know.
What is cannabis hyperemesis syndrome?
Cannabis hyperemesis syndrome is a condition affecting long-term, daily marijuana users that can cause a number of stomach-related issues.
- The only way to cure it is to stop smoking cannabis, according to the Cleveland Clinic.
- There's evidence that symptoms disappear with a hot bath or shower.
The condition affects marijuana smokers who go through a series of experiences, per the NIH, including:
- Several years of cannabis use, before the illness begins.
- A pattern of nausea and vomiting.
- Seeing symptoms die off once cannabis use ends.
Symptoms of cannabis hyperemesis syndrome
The main symptoms for CHS include:
- Ongoing nausea.
- Vomiting.
- Belly pain.
- Decreased appetite and weight loss.
The condition has been linked to heart rhythm abnormalities, seizures, kidney failure and even death.
- There's also an issue some experience called "scromiting" — a combo of "vomiting" and "screaming" that can happen for those experiencing intense levels of pain.
How does someone get cannabis hyperemesis syndrome?
Researchers are unclear what causes CHS specifically.
- One popular theory suggests that chronic cannabis use may cause "long-term overstimulation of receptors in your endocannabinoid system," which upends the body's natural control of nausea, according to the Cleveland Clinic.
Threat level: CHS doesn't affect every marijuana smoker.
- Per the Cleveland Clinic, it tends to impact people who use cannabis once a week and adults who have been smoking since they were adolescents.
The rise of CHS
The syndrome rose extensively during the COVID-19 pandemic, according to a new study published this week in JAMA.
- The jump occurred as people faced lockdowns and were staying home stressed and isolated.
- Those same patients ended up at the ER because of CHS.
The condition's rise comes as there's been a spike in THC potency, too, becoming dangerously high.
- In the '90s, 5% THC cannabis was among the strongest in products. Today, it's hard to find products with fewer than 20% THC, Axios' Carly Mallenbaum reports.
- This has led to a jump in cannabis-related trips to the ER among elderly adults.
What's next: Researchers at the University of Washington said that the WHO's new formal diagnosis will help doctors identify the syndrome when people come to the hospital.
- "It helps us count and monitor these cases," said Beatriz Carlini, a research associate professor at the University of Washington School of Medicine, in a press release.
- "A new code for cannabis hyperemesis syndrome will supply important hard evidence on cannabis-adverse events, which physicians tell us is a growing problem."
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