iopamidol

Iopamidol is a nonionic iodinated contrast agent used in radiology to enhance the visibility of vascular structures and tissues during imaging studies. It is a water-soluble compound whose radiopacity comes from iodine atoms, and it belongs to the class of low-osmolar contrast media developed to reduce adverse reactions compared with older ionic agents.

Iopamidol is prepared as injectable solutions and is commonly available in concentrations such as 300 mg of iodine per milliliter (mg I/mL) and 370 mg I/mL. It is administered intravenously or intra-arterially depending on the procedure, with use in computed tomography (CT) and angiography to delineate vessels, organs, and pathology.

Pharmacokinetics and safety: The agent distributes in the extracellular space and is excreted primarily by the kidneys. In individuals with normal renal function, clearance is rapid; in renal impairment, half-life is prolonged, increasing the risk of nephrotoxicity. Adverse effects range from mild warmth, nausea, or headache to hypersensitivity reactions; rare but serious reactions can occur. Nephrotoxicity and allergic reactions are major safety concerns; extravasation at the injection site can cause local tissue injury. Caution is advised in patients with renal disease, diabetes, dehydration, thyroid disease, or pregnancy.

Administration considerations: Use the lowest effective dose and ensure patient screening for prior iodinated contrast reactions. Hydration and avoidance of nephrotoxic drugs when possible reduce risk. Iopamidol is marketed under several brand names, including Iopamiro, and is widely used as a nonionic, low-osmolar contrast agent for imaging.