The Milk-Alkali Syndrome Caused by Betelnuts in Oyster Shell Paste

Abstract

Background: The carcinogenic effect of betelnut chewing leading to oral cancer is well known. Betelnut chewing may also affect the autonomic nervous system. In this report, we present another potential hazard of betelnuts, milk-alkali syndrome. Case Report: Two patients who had chewed a large quantity of betelnuts developed hypercalcemia, metabolic alkalosis, and renal insufficiency. They ingested a large amount of calcium carbonate from a local special paste used for betelnut preparation, the main ingredient of which is ground oyster shell. The symptoms and metabolic abnormalities disappeared promptly after abstinence from betelnut chewing and administration of saline solution. Improvement of renal function was observed in both patients. Analysis of the calcium content of the paste suggested that the patients might have ingested 9 g and 6 g of calcium carbonate per day, respectively. Conclusion: This is the first report of milk-alkali syndrome not caused iatrogenically, but by recreational usage of oyster shell preparations of betelnuts.