In vitro comparison of antifungal effects of a coal tar gel and a ketoconazole gel on Malassezia furfur.
Malassezia furfur seems to be a major pathogenetic factor in seborrhoeic dermatitis, a frequent human skin disease. To estimate the antifungal properties of a coal tar gel (5 mg ml-1 coal tar) which is used in the treatment of seborrhoeic dermatitis of the scalp, we compared its effects on the in vitro growth of M. furfur with those of a ketoconazole gel (20 mg ml-1 ketoconazole). None of the gels was fungicidal within incubation times up to 20 min. During a single application, both gels remain on the skin for only 5 min. Fungicidal effects are consequently unlikely to play a substantial therapeutic role. Fungistatic effects were observed with both gels. In cultures inoculated with 1 x 10(3) cells ml-1, a 1:49 152 dilution of the ketoconazole gel and a 1:768 dilution of the coal tar gel still showed inhibitory effects. At inoculum densities of 1 x 10(5) ml-1, both gels were fungistatic only in dilutions of a maximum of 1:40. Our results suggest that under clinical treatment conditions the fungistatic activities of both preparations should be comparable.
Wright
M C
MC
Basotherm GmbH, Biberach, Germany.
Hevert
F
F
Rozman
T
T
D003033:Coal Tar / Q000494:pharmacology*; D005782:Gels; D007654:Ketoconazole / Q000494:pharmacology*; D008290:Malassezia / Q000187:drug effects* / Q000254:growth & development; D008826:Microbial Sensitivity Tests
D005782:Gels; D003033:Coal Tar; D007654:Ketoconazole