Malassezia lipophilic fungi, formerly known as Pityrosporum, are part of the normal microflora of human skin. However, under the influence of predisposing factors, they become pathogenic and several diseases can be associated with them, such as multicolored lichen, folliculitis caused by Malassezia, seborrheic dermatitis, certain forms of atopic dermatitis and systemic infections.

Currently, many studies have been conducted showing that Malassezia plays an important role in the pathogenesis of seborrheic dermatitis. Many of these works prove the effectiveness of antifungal drugs for seborrheic dermatitis: when applied, the affected areas are cleaned, the number of Malassezia colonies decreases and the re-colonization after the treatment is stopped leads to a relapse of seborrheic dermatitis. A number of other studies have shown that the altered function of the immune system affects the pathogenicity of these yeast-like fungi.

A study by Italian scientists (Scaparro E., Quadri G, Virno G. Orifici C., Milani M) compared the oral administration of terbinafine (250 mg per day) for 4 weeks and topical placebo cream in patients with severe and severe forms of seborrheic dermatitis. 30 patients were included in each group. Oral administration of terbinafine has been shown to be effective in the treatment of seborrheic dermatitis and the effect persists for 8 weeks after treatment. According to the authors, the effect of terbinafine is due to a combination of antifungal action and anti-inflammatory activity. However, terbinafine is known to have weak activity against Malassezia fungi and is ineffective in treating multicolored lichen. Several antifungal drugs, including terbinafine, have anti-inflammatory activity in vitro and when used topically, however, there is no report on the anti-inflammatory effect of terbinafine when given orally.

It is known that ketoconazole and itraconazole administered orally are effective drugs in the treatment of seborrheic dermatitis, while they have a high activity against fungi in vitro of Malassezia. Terbinafine is not active in vitro against yeast-like fungi, although it acts on dermatophytes. In addition, the concentration of terfinadine in the skin after application of the cream is much higher than after oral administration. And although the topical use of terbinafine for seborrheic dermatitis and multi-colored lichen is effective, the data available are not sufficient to recommend this medication orally in seborrheic dermatitis (J. Faergemann).