The predominance of flunisolide in the topical use of anti-inflammatory steroids.

Local and systemic anti-inflammatory effects of topically applied flunisolide on hind footpad edema induced by subplantar injection of 1 microgram of serotonin in mice were evaluated in comparison with those of three related steroids. The order of the potency for local anti-inflammatory effect observed in the foot injected with the steroids was flunisolide, dexamethasone, betamethasone valerate and beclomethasone dipropionate in decreasing order. In contrast, potency for systemic effect of flunisolide observed on the opposite foot was rather weak compared with its strong local effect. When steroids were administered orally, the order of the anti-inflammatory potency as dexamethasone, beclomethasone dipropionate, flunisolide and betamethasone valerate in decreasing order. All of the data demonstrate that flunisolide is highly active in topical use, while systemically it is relatively weak, especially by oral administration. Those characteristics of flunisolide could be attributable to its rapid metabolic inactivation in the liver, which suggests a great advantage of its topical use in the clinical medicine.