The purpose of this study was to explore the possible comparative in-vitro effects of two anthroposophical complex preparations on the growth of Staphylococcus aureus. The effect of these two anthroposophical complexes, the first being Echinacea/ Quartz Complex Single Dose Eyedrops (Wala), and the second being a preparation called Euphrasia Single Dose Eyedrops (Wala) on Staphylococcus aureus in-vitro had not yet been established. The two methods employed were the agar dilution method and the disc diffusion method. These tests measured the in-vitro susceptibility of the Staphylococcus aureus to the anthroposophical complexes and to chloramphenicol (a broad spectrum allopathic anti-biotic commonly used to treat bacterial conjunctivitis caused by Staphylococcus aureus infection). The experiments were conducted on twenty Staphylococcus aureus isolates, obtained from Van Drimmelin Laboratories. All experimentation was conducted in triplicate in order to eliminate laboratory error. In the agar dilution method, broth cultures of the twenty isolates were prepared and equal amounts of the cultures were plated out onto the agar media individually treated with the antimicrobial of choice, or onto unmedicated agar. After 24 hours of incubation the number of colonies per plate were counted. In the disc diffusion test, discs individually impregnated with the antimicrobial of choice and unmedicated discs were placed onto inoculated nutrient agar plates. After 24 hours of incubation the zone diameters were measured. The results were compared using a two-way analysis of variance. They showed that neither of the anthroposophical complexes had a significant in-vitro effect on the growth of Staphylococcus aureus in the agar dilution method, and neither complex displayed any anti-bacterial action in the disc diffusion test. However, studies have shown that patients using these eyedrops to treat bacterial conjunctivitis have experienced significant symptomatic relief. Therefore, it is recommended that a follow on in-vivo study be conducted using these anthroposophical complexes as treatment and then growing bacterial cultures from swabs taken from the patients’ eyes at various stages of treatment to examine any anti-bacterial effects these complexes may have on Staphylococcus aureus in-vivo. / Dr. E. Solomon Dr. S. Arstall