An antimicrobial composition with synergistic biocidal activity is described which comprises at least one antimicrobial polymeric biguanide and at least one antimicrobial vicinal diol, said vicinal diol comprises at least one monoalkyl glycol, monoalkyl glycerol, or monoacyl glycerol, to diminish or eliminate biofilm communities. Such synergistic interaction is effective in wound treatment, particularly for chronic wounds, burns and battlefield-induced wounds, as well as for disinfecting non-biological surfaces. The antimicrobial composition can also be prepared as viscous solutions or as gels. The antimicrobial composition may be added to a substrate and dried, such as to a catheter, or to a foam, or to a fiber wound dressing, or coated as a viscous solution or gel upon such devices, to provide controlled release antimicrobial activity.
