Hydrocortisone 17-butyrate is a new non-fluorinated topical corticosteroid for use in psoriasis, eczema and other inflammatory dermatoses. In double-blind paired comparisons with other topical corticosteroids, the efficacy of hydrocortisone 17-butyrate 0.1% has generally been indistinguishable from that of triamcinolone acetonide 0.1%, fluocinolone acetonide 0.025% or betamethasone 17-valerate 0.1% in patients with eczema or psoriasis. When applied to the face of patients with atrophy superimposed on rosacea and perioral dermatitis resulting from prolonged use of fluorinated topical corticosteroids, hydrocortisone 17-butyrate 0.1% did not prevent the beneficial effect of systemic tetracycline nor the disappearance of telangiectasis, and tended to be more effective than hydrocortisone 1%. This result suggests that hydrocortisone 17-butyrate may be suitable for long-term use on facial lesions, although the occurrence of moderate rebound eruption in about 10% of patients indicates the need for caution. The findings suggest that hydrocortisone 17-butyrate may be less liable to cause skin atrophy and adrenal suppression than some other potent topical corticosteroids, but trials to date have been too short to allow definite conclusions regarding possible long-term effects and have not involved infants or children.