The distribution in the skin of orally active antifungals and other drugs claimed to be active in the treatment of skin diseases is of major importance, but to date has been studied only rarely. In the present study the distribution of fluconazole in stratum corneum, epidermis-dermis (without stratum corneum), eccrine sweat and serum was studied in human male volunteers after dosages of 50 mg daily for 12 days and 150 mg once weekly for 2 weeks. In the present study high levels of fluconazole were found especially in the stratum corneum. At a dose of 50 mg once daily the concentration of fluconazole after 12 days was 73.0 micrograms/g and 7 days after cessation of treatment the concentration was still 5.8 micrograms/g. At the 150 mg once a week dose the concentration 7 days after the second dose was still 7.1 micrograms/g in stratum corneum indicating that medication once a week may be effective in the treatment of dermatomycoses. High concentrations, all above the serum concentrations, were also seen in sweat and epidermis/dermis. These results indicate that fluconazole is delivered to the stratum corneum, where it is accumulated, through sweat and by direct diffusion through the dermis-epidermis. These pharmacokinetic results indicate that the drug should be very effective in the treatment of dermatomycoses. An extremely high concentration of the drug in the stratum corneum combined with concentrations from 2.93 to 4.62 micrograms/g in the rest of the epidermis and dermis is important in the treatment of these diseases.