[Resistance to griseofulvin (author's transl)].

The antibiotic griseofulvin has been used for more than two decades in the treatment of dermatophyte-induced mycoses. During the first 10 years of use griseofulvin-resistant dermatophytes were demonstrated only in a few cases. During the seventies we did not find an increase in these strains. During this period of time the total number of dermatophytes studied by us was 489 of which 5 proved resistant, that is 4 strains of Trichophyton rubrum and one strain of Trichophyton mentagrophytes, which were still growing at a concentration of 100 gamma griseofulvin per ml culture medium. We consider these strains to have a secondary resistance and did not observe dermatophytes with a primary resistance. Accordingly, the number of non-responders cannot generally be explained by the presence of resistant dermatophytes, but rather by other reasons which have already been discussed. For the time being the problem of an increasing incidence of griseofulvin-resistant dermatophytes does not exist.