What is Cannabis Hyperemesis Syndrome? Causes, Symptoms, and Treatment

Cannabis has changed dramatically over the past decade, both in the way people consume it and the potency of cannabis people have access to. As legalization has expanded across many regions, the cannabis market has grown more sophisticated and more potent. Today’s products often contain levels of tetrahydrocannabinol (THC) that are far higher than what was commonly available to people growing up in previous generations.

This has had far-reaching effects on people and communities as a whole. One of the more serious and detrimental effects of increasing use of high-potency THC is a condition known as cannabis hyperemesis syndrome, or CHS, for short.

Understanding Cannabis Hyperemesis Syndrome

Cannabis hyperemesis syndrome is characterized by repeated episodes of severe nausea, vomiting, and abdominal discomfort in people who use cannabis regularly, often daily or near daily, for an extended period of time. The hallmark features of this condition are persistent nausea, repeated vomiting, abdominal pain, and cyclical symptom patterns that can significantly impact daily functioning.[1,2]

One unique characteristic of CHS is that many individuals experience temporary symptom relief from hot showers or baths. While hot showers or baths do not treat the condition, they can provide relief and help a healthcare provider accurately diagnose the condition.

Although this condition is still not fully understood by healthcare professionals, we do know that CHS typically progresses through three stages:[3]

1. Prodromal Phase

In the prodromal phase, individuals often experience mild nausea, stomach discomfort, and reduced appetite. Morning nausea is common. Because symptoms are subtle, many individuals continue cannabis use, sometimes believing cannabis helps relieve their discomfort.

This early phase can last months or years.

2. Hyperemetic Phase

Next is the hyperemetic stage, which involves intense nausea and repeated vomiting that may occur multiple times per hour. Individuals may struggle to keep food or fluids down, leading to dehydration, dizziness, and fatigue.

Abdominal pain may occur during this stage. Additionally, this is the phase in which people may have to seek treatment from their nearest emergency room due to cyclic vomiting and dehydration.

3. Recovery Phase

The last stage is the recovery phase, which occurs when symptoms resolve after stopping cannabis use. In this phase, appetite and normal digestive function return over time, with recovery times varying greatly from one person to the next.

The Role of High-Potency THC Products in The Development of CHS

It is important to note that CHS does not occur in everyone who uses cannabis. The condition appears to affect only a subset of individuals, typically those who use high-potency cannabis for many years (typically 10 to 12 years) without breaks.[3]

Today’s cannabis market offers products with THC concentrations far exceeding those of traditional cannabis flower. Products such as concentrates and vape cartridges (commonly referred to as “carts”) can contain THC levels exceeding 70–90%. Even small amounts can deliver substantial amounts of the drug.

Additionally, there are more discreet products available on the market today, such as small disposable vapes and edible cannabis. These products may be packaged discreetly, making them look like regular sweets or legal vaping products. They don’t have an odor, making them harder to detect.

Being easier to hide than regular marijuana, these high-potency products enable individuals to use more cannabis more often throughout the day.

High-potency concentrates and vaping products produce stronger effects, which, over time, contribute to drug tolerance, meaning individuals have to gradually use larger amounts or stronger products to achieve the same effects as before. As tolerance builds, daily or near-daily use may become more common, resulting in sustained exposure to high levels of THC.

According to the CDC, 3 in every 10 people who use cannabis have a cannabis use disorder and deal with tolerance and dependency.[4]

Healthcare professionals are increasingly concerned that these patterns of frequent, high-dose exposure may play a role in disrupting the body’s naturally existing endocannabinoid system, which helps regulate digestion, appetite, and nausea.

How Can Cannabis Cause Both Nausea Relief and Nausea/Vomiting?

Cannabis is well-known in the healthcare community for its nausea-relief properties. In fact, it is used in many states as an anti-nausea medication for people undergoing chemotherapy and other treatments. As a result, people are often confused to learn that cannabis use can also lead to nausea and vomiting, as seen with CHS.

While research is ongoing, some experts believe that chronic overstimulation of this system may contribute to the paradoxical symptoms seen in CHS, including persistent nausea and vomiting despite cannabis’s well-known anti-nausea effects. In other words, short-term cannabis use may activate pathways that reduce nausea, but chronic heavy exposure can actually disrupt these pathways, leading to the opposite effects (nausea and vomiting).

Diagnosing CHS Isn’t Always Easy: Obstacles Patients Face When Seeking Treatment

Unfortunately, diagnosing CHS can be complex because symptoms overlap with many gastrointestinal and metabolic conditions.[2] Not only is this a condition with limited public awareness, but people are sometimes afraid to disclose marijuana use due to stigma, and symptom patterns can vary from person to person. Additionally, there isn’t a specific laboratory test healthcare providers can use to diagnose or rule out the condition, so they must do so based on symptoms alone.

Treatment and Recovery

The most effective treatment for CHS is stopping cannabis use. For most people, their symptoms resolve within a few weeks after doing so, but recovery time can vary.

Supportive care may be needed during vomiting episodes. This may include:

Electrolyte supplementation
Intravenous fluids for dehydration
Antiemetic medications
Nutritional counseling

Counseling and therapy can also be useful for individuals who use cannabis to manage stress, sleep concerns, or mental health symptoms. Addressing these underlying needs can support long-term recovery and reduce the risk of recurrence of both cannabis use and CHS.

How Cannabis Users Can Help Reduce Their Risk of CHS

Anyone who uses cannabis products regularly may be at risk of developing CHS. Still, cannabis remains the most commonly used drug in the United States, and in 2024, 64.2 million people reported using it that year.[5] As a result, it’s important to have harm reduction strategies available, even when using something like cannabis that many people perceive as safe or risk-free.

Harm reduction strategies to use when using cannabis include:

Avoiding frequent or heavy cannabis use
Taking regular tolerance breaks (not using cannabis products for a minimum of 2-4 weeks at a time to let your body reset)
Staying aware of the potency/THC levels of the cannabis products you consume
Choosing lower-THC products
Only using cannabis on special occasions rather than daily use
Having regular visits with your primary care physician and treating any existing mental or physical health conditions as symptoms arise
Being honest with your healthcare providers about your cannabis consumption

Where to Find Support When You Need It

If you or someone you care about is experiencing symptoms related to cannabis use or wants support in making healthier choices, help is available. Visit https://apcbham.org/findhelp/ to find help for teens, parents, yourself, and more.

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