An anti-microbial preservative for use in ophthalmic and dermatologic products. The preservative includes from about 0.005 wt. % to about 0.20 wt. % chlorite compound and from about 0.005 wt. % to about 0.05 wt. % peroxy compound. Additionally, the preservative does not generate chlorine dioxide within the pH range of 5.0-8.8. Also included are an antimicrobial ophthalmic and dermatologic compositions for direct application onto an eye or skin of a living being including from about 0.005 wt. % to about 0.20 wt. % chlorite compound and from about 0.005 wt. % to about 0.05 wt. % peroxy compound. Also included are methods for treating dryness of the eyes and skin disorders (e.g., wounds, burns, infections, ulcerations, psoriasis, etc.) and for disinfecting and cleansing contact lenses while in place upon an eye by applying the composition to the eye or to the contact lens.