The United States has recorded a sharp rise in hospital visits linked to nausea and vomiting among frequent marijuana users.
A report released Thursday by the US Centers for Disease Control and Prevention found that emergency room diagnoses of cannabis hyperemesis syndrome increased 16% from October through May.
The condition affects people who use marijuana frequently. It can cause repeated nausea, severe vomiting and intense abdominal pain.
Marijuana Users Nausea Cases Rise After New Diagnosis Code
Researchers say the sudden increase does not necessarily mean the condition itself became more common.
Instead, the rise is largely linked to a new diagnosis code introduced last October.
The code made it easier for doctors and hospitals to identify cannabis hyperemesis syndrome. As a result, health officials now have a clearer picture of a problem that may have been underdiagnosed for years.
Before the new code, doctors had to combine separate codes for nausea, vomiting and cannabis use.
Cannabis Hyperemesis Syndrome May Be Underdiagnosed
Previous research estimated that about 2.75 million Americans may experience cannabis hyperemesis syndrome each year.
Emergency room visits linked to the condition have also increased as daily recreational marijuana use has become more common.
However, experts believe many cases may have gone undetected.
Doctors may not always have known about a patient’s marijuana use. In other cases, they may have linked the symptoms to another medical condition.
The new diagnosis code has made tracking the syndrome much easier.
Younger Marijuana Users See Sharp Increase
CDC researchers examined emergency room data from around 7,500 healthcare facilities across the country.
From January 2023 through the summer of 2025, nearly 200,000 emergency department visits were linked to the syndrome.
For much of that period, the number of visits remained relatively stable.
However, diagnoses increased sharply in October after the new code came into effect.
The biggest increases occurred among people aged 15 to 24. Teenage girls and women also recorded notable increases.
Researchers also found higher increases among Black Americans and American Indian and Alaska Native people.
CDC Calls for More Research on Marijuana Use
The increase among younger patients surprised researchers.
Alana Vivolo-Kantor, the study’s lead author, said the findings raised questions about how early some young people begin using cannabis.
The CDC report highlights the need for greater awareness of cannabis hyperemesis syndrome, particularly among teenagers and young adults.
Researchers also want more studies into newer high-potency THC products.
These products include vapes, drinks and gummies made with THC or hemp-derived ingredients.
Health officials say more research is needed to understand how these products are used and how they may affect younger Americans.
For frequent marijuana users, recurring nausea, vomiting and severe abdominal pain can be warning signs of cannabis hyperemesis syndrome and should not be ignored.
