Serum sickness is an immune-complex mediated illness that frequently occurs in patients after polyclonal antibody therapy (ATGAM or thymoglobulin). Serum sickness presents with significant morbidity but is self-limited and resolves with prolonged steroid therapy. We present five renal transplant patients who developed serum sickness after polyclonal antibody treatment with severe symptoms that persisted after being started on systemic steroids. These patients underwent one or two courses of therapeutic plasma exchange (TPE) with subsequent complete resolution of their symptoms. Renal transplant recipients with serum sickness after polyclonal antibody therapy may benefit from TPE by accelerating their time to recovery and thereby reducing overall morbidity.