Urinary and Plasma Profiles of Betamethasone and Triamcinolone Acetonide Following Intra‐Articular and Related Administrations

Since 2022, intra-articular (IA) and periarticular (PA) administrations of glucocorticoids (GC) have been prohibited in sports during competitions. The aim of this study was to evaluate plasma and urinary concentrations of betamethasone (BET) and triamcinolone acetonide (TA) following IA and PA administrations, in order to verify the suitability of the minimum reporting levels (MRL) and washout periods established by WADA and to assess their systemic effects. Urine and plasma samples were collected after IA or PA administration in patients or athletes receiving GC treatment. For BET, 12 participants received IA, and 20 received PA injections; for TA, eight participants received IA, and six received PA administrations. Sample analysis was performed using validated LC-MS/MS methods. The elimination profiles of BET after both IA and PA administrations were comparable, with high concentrations observed during the first postadministration day followed by a progressive decline. Similar plasma concentrations were obtained after both routes, with a similar effect on cortisol levels, indicating a clear systemic effect. For TA, different excretion patterns were observed depending on the administration route. After IA injections, TA displayed a profile similar to that of BET. In contrast, following PA administration, TA concentrations in urine and plasma were lower and remained relatively constant over several days. The degree and duration of cortisol suppression after PA administration varied among participants, with some showing a short effect. The results obtained support the MRL for IA and PA administrations defined by WADA. However, the washout period for BET is recommended to be increased to 5 days.