RESUMO
BACKGROUND: Resistance to antibiotics is a major public health concern worldwide. New treatment options are needed and homeopathy is one such option. We sought to assess the effect of the homeopathic medicine Belladonna (Bell) and a nosode (biotherapy) prepared from a multi-drug resistant bacterial species, methicillin-resistant Staphylococcus aureus (MRSA), on the same bacterium. METHODS: Bell and MRSA nosode were prepared in 6cH and 30cH potencies in 30% alcohol and sterile water, according to the Brazilian Homeopathic Pharmacopeia and tested on MRSA National Collection of Type Cultures (NCTC) 10442. We assessed in vitro bacterial growth, deoxyribonuclease (DNAase) and hemolysin activity, and in vitro bacterial growth in combination with oxacillin (minimum inhibitory concentration - MIC). All values were compared to control: 30% alcohol and water. RESULTS: In vitro growth of MRSA was statistically significantly inhibited in the presence of Bell and nosode 6cH and 30cH compared to controls (p < 0.0001); and with combination of Bell or nosode 6cH and 30cH and oxacillin (p < 0.001). Bell 30cH and nosode 6cH and 30cH significantly decreased bacterial DNAse production (p < 0.001) and reduced red blood cell lysis. CONCLUSIONS: Cultures of MRSA treated with Belladonna or MRSA nosode exhibited reduced growth in vitro, reduced enzymatic activity and became more vulnerable to the action of the antibiotic oxacillin. Further studies are needed on the biomolecular basis of these effects.