What is Cannabinoid Hyperemesis Syndrome?

abdominal pain from cannabis
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The cannabis industry continues to gain momentum across the United States. With the further adoption of cannabis-friendly laws and cultural attitudes, so too has research on the subject increased. The benefits and therapeutic value of cannabis are continually being studied and evaluated, and we are far from knowing everything. Indeed, Cannabinoid Hyperemesis Syndrome (CHS) is one of these recently observed cannabis-related health mysteries. Unfortunately, as it is currently understood, CHS is decidedly less than favorable but has the upside of being easily treatable. Here is what we know:

The Paradox of CHS

Cannabinoid Hyperemesis Syndrome is not experienced daily; rather, it has been observed in periods. Symptoms may arise one month, stay for a week (as long as cannabis use continues), and disappear for another arbitrary amount of time. Research on the topic is minimal, and often the cannabinoid syndrome itself is easily misdiagnosed with other similar conditions. 

If broken down at pharmacological basis of action, many of the world's most used drugs have a point where the desirable effects are reversed or outweighed by the undesirable. Some of these are short-term, others long. With caffeine, frustration, anxiety, and sleep loss may occur if you consume too much. Nicotine in small amounts is addictive to be sure, though it remains largely nontoxic in the short term. At higher levels, however, nicotine becomes able to disrupt entire body systems, becoming very toxic.

Each of these chemicals causes a unique reaction in the brain, either causing, stimulating, blocking, or interrupting normal neurotransmission. Neurotransmission, if put simply, is a process of transmitting information between nerve cells. A number of effects can arise from this. Some may be positive, such as increased energy or mood. Others, such as fatigue or anxiety, are less rewarding. Additionally, the change in neurotransmission may affect other, less obvious functioning of the body.

Less of one neuron firing can cause a nutrient to not be absorbed, leading to the synthesis of a hormone or enzyme not being completed as needed, leading down a complex string of interactions each with the potential to cause further irregularities in the equilibrium of healthy daily life.

Cannabinoid Hyperemesis Syndrome, however, differs greatly from caffeine or nicotine in its acuteness, often taking years to decades to develop rather than minutes or hours. Furthermore, CHS does not seem to be linked to the amount of cannabis someone consumes, only the frequency and length of use.

So what is Cannabinoid Hyperemesis Syndrome? 

brain neuron
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First defined as a unique and separate condition in 2004, medical researchers in Australia became intrigued by the highly infrequent – though potentially significant – complaint by long-term cannabis users of severe vomiting and nausea. The habit of using cannabis daily and abrupt, infrequent, and severe bouts of vomiting and nausea, researchers reasoned, may be related.

It turned out, they are.

True enough, cannabis is used by medical marijuana patients across the US to treat nausea and vomiting. Cannabis is used medicinally help prevent wasting syndrome (rapid weight loss due to vomiting) in HIV patients, to ease nausea associated with chemotherapy, as well as in the treatment of several gastrointestinal conditions.

It's a medical paradox, of sorts.

Medical professionals studying Cannabinoid Hyperemesis Syndrome have created three categories of symptoms: 

  1. The Prodromal Phase
  2. The Hyperemetic Phase
  3. The Recovery Phase

The Prodromal Phase

The prodromal phase is defined by morning nausea and abdominal pain, often accompanied by the lingering idea of vomiting. Eating is not an issue at this point. This period may last for months, if not years, before progressing.

While there is only a small amount of hard data on the subject, it is believed the average time before a person susceptible to Cannabinoid Hyperemesis Syndrome first recognizes the condition is 16 years.

A vast majority of cannabis users, it seems, are totally unaffected.

The Hyperemetic Phase

Hyper, meaning excessive, beyond, or above normal, and emetic, defined as causing involuntary vomiting, this phase is much shorter in duration than the prodromal phase.

During the hyperemetic phase, symptoms often include:

  • Persistent nausea
  • Episodes of vomiting
  • Pain in the abdomen
  • Troubles eating
  • Weight loss
  • Dehydration

An interesting behavior common among those suffering from Cannabinoid Hyperemesis Syndrome during this phase is to take excessive hot showers or baths. Sometimes patients do this for hours at a time or multiple times daily, hoping to relieve the nausea. At the point, the vomiting is considered overwhelming.
Researchers believe hot baths and showers may help ease symptoms due to the effect temperature has on the hypothalamus – a section of the brain associated with temperature regulation and vomiting.

The worst part?

Research data shows most patients experience little to no relief from traditional medications for nausea and vomiting. In most cases, medications used to treat such conditions do nothing for the individual to stop. The best and most effective treatment for Cannabinoid Hyperemesis Syndrome it seems is to – unfortunately – quit using marijuanaentirely.

The Recovery Phase

The worst of the hyperemetic phase ends typically within two days of stopping marijuana use, ushering in the recovery phase. As the name suggests, the recovery phase is a period when nausea, vomiting, and abdominal pain largely disappear. Eating can return to normal, while weight loss and symptoms of dehydration quickly disappear. Lasting days to months, the recovery phase is sustained by discontinuing the use of cannabis products entirely.

Additionally, research shows resuming marijuana use typically will cause the symptoms of Cannabinoids Hyperemesis Syndrome to return – but not always.

What Causes It?

Little is known about why Cannabinoid Hyperemesis syndrome only affects certain individuals, or why it occurs only after years of daily use. Furthermore, only a few hypotheses have been offered to explain why the condition arises. As cannabis is only of the most commonly used drugs in the world, the fact the condition has very little substantive information on its pathophysiology is surprising.

One hypothesis regarding the condition describes a scenario where, just as cannabinoids can affect neurotransmitters in the brain and central nervous system, so to can they affect nerves in the gastrointestinal tract. It is thought the infrequent use of marijuana in susceptible populations may not lead to the symptoms of Cannabinoid Hyperemesis Syndrome and may, in fact, reduce nausea and vomiting.

However, some cannabinoids have been shown to change or slow the motility of the digestive tract. With persistent use of cannabis, some individual's digestive tract may be thrown out of homeostasis, causing the body to ineffectively use energy and resources. Nausea and vomiting may occur as a response to persistent overstimulation of the endocannabinoid system, where cannabinoids can most readily attach.

Having been knocked out of homeostasis, the puking and nausea may be related to an internal 'reset' button trying to get the body into proper working order once more. But this, of course, is merely anecdotal.

At this point, what can be said for certain our understanding of Cannabinoid Hyperemesis Syndrome is limited and is more research is necessary.