:Different adverse reactions to silicone present in cosmetic fillers, implants, or medical devices have been reported. The granulomatous reaction on the injection site due to catheters' silicone coating is an infrequent complication, which may be clinically difficult to suspect. Although the definitive diagnosis requires identification of the silicone with techniques such as X-ray spectroscopy, the possibility of involvement of silicone, as well as the histopathologic demonstration of granulomas with refractile, nonpolarizable, and nonstainable material strongly suggests this diagnosis. Moreover, the use of a low-diaphragm aperture or phase-contrast microscopy could be useful to demonstrate the presence of this, otherwise almost transparent, foreign body.