An intravenous infiltration detection apparatus for monitoring intravenous failures, which applies an optical method coupled with fiber optics and algorithms for tissue optics to provide a means for noninvasive detection of intravenous infiltration surround the site of IV injection. In the invention, the tissue surrounding the injection site is exposed to a single-wavelength of electromagnetic radiation, and light is collected with only one detector. Changes in the relative intensity of the radiation reflected, scattered, diffused or otherwise emitted provide a means for monitoring infiltration. The invention provides routine, automated, continuous, and real-time monitoring for patients undergoing IV therapy.