Nosocomial infections have emerged as important causes of morbidity and mortality in immunocompromised individuals. In this respect, biocides are widely used in hospitals leading to resistant microorganisms. We show here that cyclodextrins can remarkably boost the virucidal activity of di-n-decyldimethylammonium chloride. These oligosaccharides synergistically work with the biocide affording a noticeable reduction of the active virucide concentration between 40 and 85%. Partial replacement of a significant amount of the biocide by eco- and bio-compatible cyclodextrins whilst maintaining the same activity is of great interest as it allows the reduction of the toxicological drawbacks of classical biocide mixtures.