Lack of gastric effects of S-(carboxy-methyl)-L-cysteine

In 10 male subjects, the effects of oral S-(carboxy-methyl)-L-cysteine (SCMC) -- a mucolytic agent useful in the treatment of chronic obstructive bronchitis -- on gastric secretion of acid and N-acetylneuraminic acid (NANA) containing glycoproteins were investigated. Gastric acid outputs and mucus secretory rates remained unchanged during a 10-day period of daily administration of SCMC. Thus, the receptors of SCMC in the bronchial system appear to differ basically from those in the stomach.