Cyanoacrylate adhesive compositions comprise a mixture of two cyanoacrylate monomers, including 2-octyl cyanoacrylate and n-butyl cyanoacrylate. The monomers are stabilized and sterilized by irradiation, and do not substantially increase in viscosity after sterilization or after two years of shelf storage. These compositions have anti-microbial properties, and may be used to close wounds as well as secure catheters inserted into the body in place.