Bovine respiratory disease (BRD) is the leading cause of illness and death in U.S. cattle. The disease results from a complex interaction between infectious viral and bacterial pathogens, the environment, and the host. It is often initiated when an animal is exposed to one or multiple stress contributors which cause the animal’s immune system to be suppressed, allowing viral or bacterial agents to initiate infection in the body. Non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to be a useful method for treating BRD when used in adjunct to antibiotics (Lockwood et al., 2003; Friton et al., 2005). These drugs do not impair the immune system, and they have pain and fever reducing effects. Corticosteroid pharmaceuticals have also been used as ancillary therapy, but studies have yielded conflicting results (Bednarek et al., 2003; Sustronck et al., 1997). These drugs have anti-inflammatory properties, and isoflupredone acetate is a corticosteroid that has shown notable results when used as ancillary therapy in treatment of BRD in a challenge model study conducted by Hewson et al., 2011. Isoflupredone acetate is approved in the U.S. for food animal use and has label indications for critical infections in cattle. Therefore, the study objective was to evaluate the use of isoflupredone acetate as ancillary therapy in the treatment of naturally occurring bovine respiratory disease in newly received stocker calves.