When Cannabis Vomiting Gets So Bad It Causes Brain Damage

Single case report of a woman in her 20s presenting with Wernicke's encephalopathy secondary to thiamine deficiency caused by prolonged vomiting from cannabinoid hyperemesis syndrome. Diagnosis confirmed by brain MRI showing T2/FLAIR symmetric thalamic hyperintensities.

Most CHS discussions focus on the vomiting itself and the relief from hot showers. This case reveals a downstream risk that clinicians may not anticipate: prolonged CHS vomiting can cause nutritional deficiencies severe enough to produce brain damage. It also highlights that Wernicke's encephalopathy should be on the differential diagnosis for any patient with prolonged vomiting and new neurological symptoms—not just alcoholic patients.

CHS has become increasingly recognized as cannabis potency and use frequency have risen (see RTHC-00162 on increasing cannabis-related emergency visits). This case adds a new dimension to the CHS clinical picture—it's not just about managing vomiting and dehydration, but about preventing the nutritional complications that can follow prolonged emesis. The Wernicke's encephalopathy connection also parallels how other chronic conditions (eating disorders, bariatric surgery, hyperemesis gravidarum in pregnancy) can cause thiamine deficiency through the same mechanism.

Single case report—cannot establish how common this complication is among CHS patients. No information on the patient's cannabis use patterns (frequency, potency, duration). The dramatic response to thiamine confirms the diagnosis but doesn't tell us whether early supplementation could have prevented the neurological complications.