The effect of topical steroids on cutaneous oxygen tension

The precise mode of action of topically applied steroids is unknown. We have applied clobetasol propionate 0.05% ointment (Dermovate; Glaxo Pharmaceuticals) under occlusion to the forearm skin of 10 healthy volunteers for 6 h and monitored transcutaneous oxygen tension at the site for 19 h after its removal. Compared to the ointment base, the steroid-treated area was significantly hypoxic up to 13 h after application. The profound hypoxia present at the site of application of clobetasol propionate 0.05% ointment may account for some of its anti-inflammatory effects, and its atrophogenicity.