Polyhexanide and betaine topical solution is used in the management of infected wounds as a cleaning agent. An in vitro study was conducted to examine the antimicrobial effects of a solution containing 0.1% of the antimicrobial agent polyhexanide and 0.1% of the surfactant betaine. Three batches of each product were tested, and culture results of 13 microorganisms were evaluated after 7, 14, and 28 days using USP <51> methodology. Growth reduction was identical at each day following exposure to the solution in all micro-organisms except Aspergillus brasiliensis. A range of 5.3-log to 5.8-log reduction was seen for the following micro-organisms: Staphylococcus epidermidis, Pseudomonas aeruginosa, Serratia marcescens, Candida albicans, S. aureus, vancomycin-resistant Enterococcus faecalis, Proteus mirabilis, Escherichia coli, methicillin-resistant S. aureus, Acinetobacter baumannii, Enterobacter cloacae, and E. faecalis. For A. brasiliensis, reductions were 2.1-log, 2.3-log and 2.8-log at 7, 14, and 28 days, respectively. The results of this study indicate a 4+ log inhibition of activity in 12 of 13 micro-organisms exposed to the solution. Research to elucidate the potential clinical effects of these observations is needed.