Which of the following iodinated contrast media is classified as a NON-IONIC, LOW-OSMOLAR agent?

• A Diatrizoate
• B Metrizoate
• C Iothalamate
• D Iohexol ✓

Explanation

Iohexol is a non-ionic monomer with osmolality roughly one third that of conventional high-osmolar agents, placing it in the low-osmolar class used routinely today. Diatrizoate and iothalamate are ionic high-osmolar monomers, and metrizoate is an ionic monomer as well. The ionic versus non-ionic distinction matters because non-ionic agents have far lower chemotoxicity and much lower rates of adverse allergic-like reactions.

Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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