Summary

While bortezomib is known to cause adverse effects involving the autonomic nervous system, gastrointestinal side effects are typically mild. We describe herein a series of patients with myeloma and impaired renal function who developed severe paralytic ileus secondary to bortezomib use. Our patients had other risk factors for paralytic ileus including electrolyte abnormalities and opiate use. The striking commonality in our patients is the development of paralytic ileus with intravenous bortezomib in the setting of reduced renal function, followed by ileus resolution with bortezomib dose reduction. We discuss the existing literature on this subject and propose a strategy in order to reduce the risk of paralytic ileus in these patients. Upfront bortezomib dose reduction to 1 mg/m² intravenously in patients with myeloma with a glomerular filtration rate (GFR) of <30 mL/min may prevent paralytic ileus, while not compromising the clinical outcomes. Our conclusions will have to be validated in larger studies.