The potency of clobetasol propionate: serum levels of clobetasol propionate and adrenal function during therapy with 0.05% clobetasol propionate in patients with severe atopic dermatitis

BACKGROUND: Percutaneous absorption of topically applied 0.05% clobetasol propionate (CLO) can be assessed indirectly by measuring cortisol levels. A direct way is to measure systemic levels of topically applied CLO.

METHODS: Serum concentrations of CLO were measured by liquid chromatography-tandem mass spectrometry (LC/MS/MS), and were related to serum cortisol levels in 25 patients with an exacerbation of atopic dermatitis (AD) before and after the first day of treatment with 0.05% CLO in hospital. The body surface area (BSA) affected by AD was measured.

RESULTS: Before the start of 0.05% CLO treatment, normal cortisol levels were measured (0.47 ± 0.18 μmol/l) and CLO concentrations could not be detected. After the first day of treatment, cortisol levels decreased to 0.04 ± 0.05 μmol/l. Serum concentrations of CLO could be detected in all patients (0.112-4.504 ng/ml). Levels did not differ between patients who had received two applications versus one application of 0.05% CLO. There was no correlation between the affected BSA and serum concentrations of CLO.

CONCLUSION: Serum levels of CLO can be measured by LC/MS/MS. When prescribing 0.05% CLO, one must bear in mind that, even after an application of 20-30 g, CLO is systemically available and potent enough to induce adrenal gland suppression.