Although it is well known that zinc ions and the oxines form practically insoluble chelates, oxines are commonly used in combination with zinc oxide in ointment form. 13 patients who had shown allergic responses after epicutaneous testing with oxines were tested with iodochloroxine and certain combinations of it with starch, titanium dioxide and zinc oxide. The allergic reaction to iodochloroxine was suppressed when zinc oxide was present but was uninhibited in the other tests. Certain metal ions lower the fungicidal and bactericidal effects of oxines. Zinc oxide alone showed some inhibitory effect upon Trichophyton and Epidermophyton but stimulated the growth of Candida strains. The propagation of dermatophytes was greater with a combination of iodochloroxine and zinc oxide than with either substance alone. If the concentration of iodochloroxine was considerably higher, Candida grew when zinc oxide was also present.