The FDA cited Baxter Healthcare for selling an infusion pump without premarket approval. As a result, the company's SIGMA Spectrum Infusion Pump with Master Drug Library is also misbranded, regulators allege in an April 1, 2013, warning letter addressed to Baxter CEO Robert Parkinson, Jr. As with all companies facing warning letter citations, Baxter had 15 days to respond to the FDA, outline steps taken to correct violations and also detail plans to prevent future problems. Warning letter