Abstract It has been suggested that potency of corticosteroids should be determined by comparison of several parameters. To test this hypothesis, four corticosteroids were studied in two animal test systems and relative potency ratios were determined. Relative potency ratios for anti-inflammatory activity were determined in an immunogenic uveitis test in rabbits. The effect of topical applications of corticosteroids on rabbit outflow facility was also studied. Comparison between the potencies obtained in each test system showed that, although a corticosteroid may have potent anti-inflammatory activity, commensurate adverse effect on outflow facility may also be present. Conversely, a corticosteroid showing low potential to affect outflow facility may also show low anti-inflammatory activity. It was also demonstrated that the two potency ratios for the same compound are not necessarily concurrent.