Aims: To compare the ability of an amorphous first aid topical gel containing vinegar, citric acid and EDTA (RescuDerm (TM); RESC) and various derivative formulations to eradicate Pseudomonas aeruginosa (PSEUD) and Staphylococcus epidermidis (STAPH) biofilms. Methods and Results: 24-h biofilms prepared using the Minimum Biofilm Elimination Concentration (MBEC (TM)) Assay System were exposed for 4 or 24 h to the different gel formulations. Citric acid-free, acetic acid-free or acetic acid-free/sodium acetate-supplemented RESC gels reduced PSEUD and STAPH biofilm formation as effectively as RESC. Substituting the weak organic acids with equivalent concentrations of glacial acetic acid reduced the effectiveness of gel against PSEUD and STAPH biofilms by half, but viable bacterial counts still remained below 4 log(10) CFU/peg. Removal of gelling agent and/or EDTA enhanced efficacy against PSEUD but not STAPH biofilms. An acidified placebo gel formulation generated an only marginal bactericidal effect compared to that of RESC. Conclusions: RESC is a promising new antimicrobial agent. Its weak organic acid content, rather than merely acidic pH, mediates its considerable in vitro bactericidal efficacy against bacterial biofilms. Significance and Impact of the Study: These data, taken together with the observation that RescuDerm (TM) possesses broad in vitro bactericidal activity against other pathogen species, suggest the potential usefulness of this product for controlling biofilm formation on a variety of cutaneous traumatic and surgical wounds.