N-acetylcysteine (NAC)
An amino acid that enhances the production of glutathione; sometimes taken orally as a treatment for blepharitis & meibomian gland dysfunction.
EXTERNAL LINK: AgingEye.net page on blepharitis (scroll to "Antioxidant treatment")
STUDY: N-acetylcysteine in chronic blepharitis. Yalcin E, Altin F, Cinhuseyinoglue F, Arslan MO. Cornea, 2002 Mar;21(2):164-8.