Abstract
The increasing availability of cannabidiol (CBD) products worldwide has raised concerns about their safety profile; although CBD is generally considered safe, adverse effects have been reported, particularly from overdose. This report describes a rare case of a 26-year-old male who ingested a small amount of CBD gummies (40 mg) and developed marked tachycardia, complete right bundle branch block (CRBBB), and lactic acidosis. The patient presented with nausea and vomiting, heart rate increased from a normal 80 bpm to 165 bpm, 12-lead ECG confirmed CRBBB, and laboratory tests showed elevated lactate levels indicative of type B lactic acidosis without shock or ischemia. Symptoms resolved with supportive care, including intravenous fluids, and the patient’s cardiac conduction returned to normal within a week. This case highlights the potential for serious cardiovascular and metabolic complications from CBD gummy ingestion in Japan. These findings underscore the need for awareness among healthcare professionals of the potential side effects of CBD gummies, even in small doses. Close monitoring and supportive care are essential to manage these cases, and further research is needed to clarify the mechanisms of these effects and ensure the safety of CBD products.