From the Guidelines
Hyperemesis cannabinoid syndrome (CHS) should be suspected in patients with chronic nausea and vomiting and a history of cannabis use, and the only definitive treatment is complete cannabis cessation. The diagnosis of CHS can be challenging due to the perceived anti-nausea effects of cannabis and patients' reluctance to associate their symptoms with cannabis use 1. The clinical diagnostic criteria for CHS include cyclic vomiting, nausea, and abdominal pain, and in some cases, prolonged bathing behavior (long hot baths or showers) 1.
Pathophysiology and Diagnosis
The pathophysiology of CHS involves dysregulation of the endocannabinoid system from chronic THC exposure, particularly affecting the hypothalamus and digestive tract 1. The main active ingredient in cannabis, D9THC, activates 2 G-protein–coupled membrane receptors, CB1 and CB2 receptors, with CB1 receptors being the predominant receptors involved in the effects of THC resulting in nausea or vomiting 1.
Treatment and Management
Treatment typically involves complete cannabis cessation, which remains the only definitive intervention 1. Acute management includes IV fluids for dehydration, anti-emetics like ondansetron (4-8mg every 6 hours), and hot showers or capsaicin cream (0.075% applied to abdomen 3-4 times daily) for symptomatic relief through TRPV1 receptor modulation 1. Benzodiazepines like lorazepam (1-2mg) may help with associated anxiety.
Key Considerations
Key considerations in the diagnosis and management of CHS include:
- A thorough history of cannabis use and symptoms
- Recognition of the cyclic nature of vomiting and abdominal pain
- Association with prolonged bathing behavior (long hot baths or showers)
- Complete cannabis cessation as the only definitive treatment
- Acute management with IV fluids, anti-emetics, and symptomatic relief measures 1.
From the Research
History of Hyperemesis Cannabinoid
- Hyperemesis cannabinoid, also known as cannabinoid hyperemesis syndrome (CHS), is a condition associated with cannabinoid overuse, characterized by cyclical vomiting, diffuse abdominal pain, and relief with hot showers 2.
- The first reports of CHS emerged in the early 2000s, but it wasn't until 2018 that a novel treatment guideline was established to unite the emergency department community in the treatment of CHS 2.
Symptoms and Diagnosis
- CHS typically presents with intractable nausea, vomiting, and abdominal pain, which can be resistant to standard antiemetic therapy 3, 4.
- Patients often undergo extensive evaluations, including laboratory examinations, advanced imaging, and unnecessary procedures, before being diagnosed with CHS 2.
- The diagnosis of CHS is primarily based on clinical presentation and a history of chronic cannabis use 2, 3, 4.
Treatment Options
- Capsaicin, a readily available topical preparation, is a reasonable first-line treatment for CHS, providing symptom relief in some patients 2, 3, 4.
- Antipsychotics, such as haloperidol and olanzapine, have been reported to provide complete symptom relief in limited case studies and may be effective in treating CHS 2, 3, 5, 6.
- Conventional antiemetics, including antihistamines, serotonin antagonists, dopamine antagonists, and benzodiazepines, may have limited effectiveness in treating CHS 2, 4.
- Opioids should be avoided in the treatment of CHS, as they may exacerbate symptoms and lead to further complications 2, 5.
Recent Studies
- A 2021 randomized controlled trial found that intravenous haloperidol was superior to ondansetron in reducing abdominal pain and nausea in patients with CHS 5.
- A 2023 case series reported the successful use of haloperidol, lorazepam, and/or capsaicin in treating adolescent patients with CHS 3.
- A 2021 case series found that olanzapine was effective in treating refractory CHS, particularly in cases with comorbid psychotic symptoms or agitation 6.