Cannabinoid hyperemesis syndrome is an underrecognized condition associated with recurrent vomiting and abdominal pain in individuals with prolonged cannabis use. This study used an internet-based survey targeting individuals with self-reported cannabinoid hyperemesis syndrome to assess the burden of disease and to examine associations between heavy cannabis use, early initiation of cannabis use, and cannabinoid hyperemesis syndrome episode frequency. A total of 1,052 participants were included, with the majority reporting frequent cannabis use and significant health care utilization, including emergency department visits and hospitalizations. This study highlights the substantial disease burden associated with cannabinoid hyperemesis syndrome in an online support group cohort and underscores the possible risks of heavy daily cannabis use and of use starting in adolescence. Future studies on heavy cannabis users are necessary to further elucidate cannabinoid hyperemesis syndrome and its link to daily cannabis use and the dangers of heavy use in adolescence.