FDA Warns Certain Ultrasound Contrast Agents Can Lead to Potentially Deadly PEG Allergic Reactions WASHINGTON D.C. - The Food and Drug Administration (FDA) recently issued a warning to healthcare professionals that certain ultrasound contrast agents such as Definity, Definity RT, and Lumason, contain polyethylene glycol (PEG) … [Read more...] about FDA Warns of Deadly Allergies Caused by PEG-containing Ultrasound Contrast