Though widely known for its anti-nausea and antiemetic properties, cannabis use can cause cyclical bouts of severe stomach pain, nausea, and vomiting in heavy users—a condition otherwise known as cannabinoid hyperemesis syndrome (CHS).
As more states continue to legalize cannabis, cannabis use among Americans has increased considerably. Moreover, most cannabis products today contain much higher concentrations of tetrahydrocannabinol (THC) than they did in the 1980s and ‘90s.
With cannabis stronger and more popular than ever before, rising cases of cannabinoid hyperemesis syndrome have sparked both interest and concern from researchers and emergency healthcare providers in recent years.
Understanding CHS
In terms of discovery, CHS is still a relatively new condition. According to the American Journal of Therapeutics, one of the first cases of CHS was reported in 2004. Due to a lack of research and recognition, most of what is known about CHS comes from anecdotal evidence and patient case reports.
As a result, why and how cannabinoid hyperemesis syndrome occurs is still unclear to researchers and healthcare providers. However, two theories on what causes CHS have emerged over the last decade.
One theory suggests that CHS is a “withdrawal-type syndrome” caused by consistent stimulation of cannabinoid receptors in the central nervous system (CNS) and enteric plexus. The enteric plexus is a part of the nervous system that controls gastrointestinal functions and muscles.
Some researchers believe that the increased potency of cannabis can adversely affect the body’s cannabinoid receptors. They theorize that in heavy marijuana users, chronic stimulation of cannabinoid receptors can cause a “paradoxical emetic response” due to THC’s ability to interrupt gastrointestinal functions.
Symptoms of CHS
The most common symptoms of CHS include abdominal pain accompanied by nausea and severe vomiting. Diagnosis can prove challenging because its symptoms can indicate other conditions, such as cyclical vomiting syndrome (CVS).
Based on patient experiences and reported cases, CHS may also present the following symptoms:
- Gagging or dry heaving
- Excessive sweating
- Chills
- Bloating
- Heartburn or acid reflux
- Loss of appetite
- Anxiety or fear of throwing up
- Weight loss
Symptoms of CHS can last for days to months or years. The duration and severity of CHS symptoms may also depend on which stage of the syndrome the individual is experiencing.
Stages of CHS
- Prodromal phase: This stage is characterized by abdominal discomfort and morning nausea. Some may feel nauseous at the smell of food, while others may experience sweating, flushing, and excessive thirst. This phase can last for months or years, and some individuals may increase cannabis use, relying on the substance’s antiemetic properties.
- Hyperemetic phase: The hyperemesis phase of CHS is often the most intense, characterized by episodes of severe nausea and persistent vomiting and retching—often up to five times an hour. Some patients have reported experiencing up to 15 episodes in one day. Patients with CHS may also experience decreased appetite, dehydration, and mild to severe abdominal pain and often lose weight during the hyperemic phase. CHS patients typically do not experience relief from symptoms with usual antiemetics like ondansetron and promethazine. A typical habit patients develop during this period is compulsive bathing, often in hot water, to relieve symptoms. The hyperemic stage of CHS typically lasts for 24-48 hours, though the risk of relapse increases if the patient continues to use cannabis.
- Recovery phase: The third stage of cannabinoid hyperemesis syndrome usually begins with symptom management and ceasing all marijuana use. Symptom management may include intravenous electrolyte replacement, hydration therapy, and slowly reincorporating food into a patient’s diet. After patients stop cannabis use, however, they may not experience relief from symptoms for up to a week or a month, according to the Cleveland Clinic Journal of Medicine.
Risk Factors and Epidemiology
The primary risk factor for cannabinoid hyperemesis syndrome is long-term marijuana use. Long-term use is defined as 10 to 12 years of chronic use, per the Cleveland Clinic. Chronic use is characterized by marijuana consumption three to five (or more) times per day.
However, longtime cannabis users are not the only individuals who can develop CHS. CHS is common in people who use cannabis at least once a week and especially common in adults who have been using the substance since they were teens. CHS symptoms typically do not appear until after several years of chronic use.
According to the Substance Abuse and Mental Health Services Administration (SAMHSA), marijuana is the most commonly used illicit drug in the United States. However, most cases of cannabis hyperemesis syndrome go unreported due to misdiagnoses or patient reluctance to disclose marijuana use.
Diagnosis and Challenges
Because many patients may be hesitant to mention marijuana use in medical settings—despite the legalization and social acceptance of cannabis across the US—diagnosing CHS can be challenging. On the other hand, as a newly recognized condition in the medical community, few physicians consider CHS in differential diagnoses of patients presenting with nausea and vomiting.
Due to its clinical infancy, identifying cannabinoid hyperemesis syndrome often occurs as a result of ruling out other diagnoses. Patients may undergo various diagnostic evaluations such as CTs, lab tests, and endoscopies, which are usually inconclusive or negative.
In the differential diagnosis for CHS, physicians may consider other gastrointestinal conditions with similar symptoms, including the following:
- Appendicitis
- Diverticulitis
- Ectopic pregnancy
- Gastritis
- Gastrointestinal reflux disease (GERD)
- Pancreatitis
- Peptic Ulcer Disease (PUD)
- Urinary tract infection
Due to the increasing prevalence of cannabis hyperemesis syndrome, healthcare professionals have identified a handful of criteria to distinguish CHS from these other diagnoses:
- The patient has experienced symptoms for at least six months and meets other criteria for at least three months.
- The patient is experiencing episodic vomiting patterns that resemble cyclical vomiting syndrome.
- The patient began experiencing symptoms after prolonged or chronic cannabis use.
- The patient experiences relief from vomiting after “sustained cessation” of cannabis use.
- The patient resorts to “pathological” bathing, often for long periods in boiling water, for symptom relief.
Challenges Faced by Doctors in Diagnosing CHS
Perhaps the most significant challenge doctors face when diagnosing CHS is confusing the condition for cyclical vomiting syndrome (CVS). The two conditions are similar regarding symptom onset, duration, and frequency.
A unique characteristic of CHS is delayed gastric emptying and slowed bowel movements, whereas CVS patients typically experience accelerated bowel movements. Compulsive bathing is not common in those with CVS.
CVS patients also usually report experiencing chronic migraines or a family history of migraines, which are not common in patients with CHS.
Treatment and Management
Treatment of cannabinoid hyperemesis syndrome usually includes symptom management during the hyperemic phase and relapse prevention during the recovery phase. Many patients go to emergency rooms and require hospitalization during the hyperemic phase.
Although emergency departments and researchers are beginning to identify different therapies and treatment options for CHS patients, abstinence from cannabis remains the most effective treatment for the condition. Evidence demonstrates that in all cases, abstinence has led to complete symptom relief.
However, total recovery from CHS may take years for some, and emergency room visits and hospital stays usually focus on symptom management over treatment. Furthermore, many patients may not want to cease marijuana use and continue using the substance to ease their symptoms without fully understanding CHS.
Alternative Therapies for Treating CHS
While antiemetic medications often provide little to no symptom relief in patients, benzodiazepines like lorazepam (Ativan) have also been used to treat symptoms associated with CHS. A few alternative treatment options have also proven successful as CHS becomes more prevalent in ERs nationwide.
For some patients, topical capsaicin cream applied to the abdomen may alleviate pain and other symptoms. Researchers believe capsaicin works in CHS patients by stimulating the CNS’s cannabinoid transient receptor potential vanilloid receptor 1 (TRPV1).
The TRPV1 receptor affects how the body senses heat and pain, and researchers believe the effects of capsaicin cream (made from chili pepper extract) and extremely hot baths relieve CHS symptoms by working on this specific receptor.
Traditionally used as an antipsychotic, haloperidol has also been shown to resolve nausea, vomiting, and abdominal pain in CHS patients. Anesthesiologists have long used haloperidol to treat post-surgery nausea and vomiting, and it has been particularly effective in CHS patients who do not respond to ondansetron and Ativan.
Personal Stories
Although healthcare professionals are now becoming more aware of cannabis hyperemesis syndrome, thousands of people who have struggled with CHS have brought light to the topic online in recent years.
The Reddit community r/CHSinfo has grown to more than 15,000 members, and CHS is widely discussed on the r/emergencymedecine and r/EmergencyRoom subreddits.
“I was smoking daily for 10 years… After going into the hyperemesis stage for 2 weeks, it’s definitely made me quit for good,” one Redditor said in r/CHSinfo.
“Being stuck in a bathroom daily and in constant pain for 2 weeks has made me find a new appreciation for my health in general too,” they said.
“Smoking as much as I was was slowly killing me, and the relationships in my life were suffering as a result,” one Redditor commented on the post.
“Day 129 [without cannabis] here, and while there are still days that I struggle, I truly haven’t been this happy in a very long time,” the user said.
“Unfortunately, I needed something major like CHS to snap me out of my routine and make me face the consequences of my actions,” they said.
Prevention and Awareness
Many clinicians and researchers alike agree that both the increasing THC concentrations and the growing popularity of cannabis increase users’ risk of chronic use and developing CHS.
On the other hand, healthcare professionals have also recognized the importance of proper education and dispelling myths about cannabis and CHS—for both patients and the medical community.
In their systematic review of existing literature on CHS, Khattar, and Routsolias said that cannabis is often considered a “benign” substance with a low risk of addiction or adverse side effects. Because of that, they said, many people do not understand what CHS is or how it occurs.
“Ultimately, CHS should be treated as any other substance abuse problem, with early recognition, symptomatic management, and a support system to help end the addiction,” Khattar and Routsolias said.
In 2016, Pelissier et al. led a pilot study on the effectiveness of addiction specialists during CHS interventions in emergency departments. In recent years, researchers have also begun recommending substance abuse counseling and outpatient addiction treatment for CHS patients post-discharge.
Resources for those Suffering from CHS
- Cannabis Hyperemesis Syndrome in the Emergency Department: How Can a Specialized Addiction Team Be Useful? A Pilot Study
- Cannabinoid Hyperemesis Syndrome: Marijuana is Both Antiemetic and Proemetic
- Capsaicin Cream for Treatment of Cannabinoid Hyperemesis Syndrome in Adolescents: A Case Series
- Emergency Department Treatment of Cannabinoid Hyperemesis Syndrome: A Review
- Emergent Medical Illnesses Related to Cannabis Use
- HHS, SAMHSA Release 2022 National Survey on Drug Use and Health Data
Georgia’s Leader in Cannabis Addiction Treatment
Although many people believe marijuana to be safer than other illicit drugs, with the increasing popularity and potency of marijuana today, the potential dangers of excessive cannabis use are clear: chronic use may increase your risk of cannabinoid hyperemesis syndrome.
Finding compassionate care for marijuana addiction is critical for your best chance of recovery and avoiding CHS. If you or a loved one is struggling with marijuana addiction, don’t wait to seek help at The Summit Wellness Group. Reach us anytime by phone at (770) 746-9726 or by email at ContactUs@TheSummitWellnessGroup.com.