MEG hemisulfate (Mercaptoethylguanidine hemisulfate) acts as a highly potent and selective suppressor of inducible NO synthase (iNOS), demonstrating EC50 values of 11.5 μM for iNOS, 110 μM for ecNOS, and 60 μM for bNOS in tissue homogenates. It is notably effective as a peroxynitrite scavenger and blocks peroxynitrite-triggered oxidative mechanisms. Furthermore, this compound offers protective benefits across various experimental inflammation prototypes, such as ischemia/reperfusion injury, hemorrhagic shock, periodontitis, inflammatory bowel disease, and both endotoxic and septic shock.

Mercaptoethylguanidine (MEG) dihydrobromide is a selective inducible nitric oxide synthase inhibitor and peroxynitrite scavenger with potential for inflammatory bowel diseases research.