Cyclical Vomiting and Marijuana Use
Cyclical vomiting occurs when you are actively smoking marijuana, not when you stop—this is Cannabinoid Hyperemesis Syndrome (CHS), which resolves with cannabis cessation. 1
Understanding the Paradox
Cannabis causes cyclical vomiting through chronic, heavy use despite its well-known antiemetic properties at lower doses. 2 The key diagnostic features that distinguish this syndrome include:
- Stereotypical episodic vomiting occurring 3 or more times annually in patients using cannabis more than 4 times per week for over 1 year before symptom onset 1
- Resolution of symptoms after abstaining from cannabis for at least 6 months (or duration equal to 3 typical vomiting cycles) 1
- Compulsive hot water bathing for symptom relief, reported in 92.3% of cases 3 and 71% in another series 4
What Happens When You Stop Smoking
When you stop marijuana use, you may experience Cannabinoid Withdrawal Syndrome (CWS), which is entirely different from CHS. 1 CWS affects approximately 47% of regular cannabis users and includes:
- Anxiety, irritability, and gastrointestinal symptoms 5
- Nausea and stomach pain beginning after 48 hours of abstinence 4
- However, CWS does not cause the severe cyclical vomiting pattern seen in CHS 1
The critical distinction: only 1 out of 57 cannabis users with CVS (1.8%) met criteria for CHS when properly evaluated, and that single patient's symptoms resolved during abstinence and remained resolved even after resuming cannabis use. 6
Clinical Evidence Supporting Active Use as the Trigger
The 2024 AGA guidelines emphasize that cannabis cessation is the only definitive treatment to prevent recurrent episodes. 1, 7 This directly confirms that active use—not cessation—causes the cyclical vomiting. Among patients studied:
- 88% of cannabis users with CVS had abstained for longer than 1 month, but only 1 reported resolution of episodes during abstinence 6
- Most patients paradoxically report that cannabis helps control their symptoms, leading to continued use and perpetuation of the syndrome 4
The Biphasic Effect Mechanism
Cannabinoids produce a biphasic effect: low doses have antiemetic properties while high doses (typical in chronic heavy users) produce emesis. 2 Prolonged high-dose THC exposure causes changes to the endocannabinoid system via CB1 receptors, dysregulating stress responses, thermoregulation, and neurotransmitter systems. 2
Common Pitfall to Avoid
Do not confuse CHS with withdrawal symptoms. 1, 5 Patients and clinicians often misattribute CHS symptoms to other factors like food, alcohol, stress, or pre-existing GI disorders, leading to continued cannabis use and worsening of the underlying condition. 4 The syndrome is frequently underdiagnosed due to limited awareness. 4
The prevalence of CHS is rising with legalization and higher THC concentrations in modern cannabis products. 1, 4 Daily or multiple-times-daily use (median 3 times per day) with use starting before age 16 years is the typical pattern. 1