Nociception During Iodinated Contrast Medium Infusion in Computed Tomography: Neuro-physiological Mechanisms and Clinical Implications

Abstract

This article reviews the neurophysiological mechanisms underlying nociception during the infusion of iodinated contrast media (ICM) in computed tomography (CT). It describes how rapid hemodynamic and osmotic changes activate vascular nociceptors, generating transient sensations such as intense warmth, urinary urgency, metallic taste, dry mouth, and mild discomfort or pain. Although these responses do not correspond to true pathological pain, they can influence patient comfort and, indirectly, image quality. The paper also discusses differential diagnosis and management strategies—including pre-procedural education, environmental reassurance, and adjustment of injection parameters—to mitigate these transient manifestations and optimize diagnostic outcomes.