Safety of positive gastrointestinal contrast media. Updated guidelines by the ESUR Contrast Media Safety Committee

Many reports on adverse effects related to positive gastrointestinal (GI) contrast media (CM) predate 2000; therefore, a literature review on their current safety profile was warranted. This article reviews the literature and updates the Contrast Media Safety Committee guidelines of the European Society of Urogenital Radiology on the safety of positive GI iodine-based and barium sulphate-based CM. A systematic literature search (2000-2025) identified 2 randomised controlled trials, 2 comparative studies, 17 reviews, and 29 case reports on the adverse effects of positive GI CM. Enteric non-ionic iodine-based low- and iso-osmolar CM are more palatable than ionic hyperosmolar agents (HOCM) and are preferred for oral use. The most frequent adverse effects of enteric ionic iodine-based HOCM are nausea, diarrhoea, vomiting, abdominal pain, and unpleasant taste, while pulmonary complications following aspiration are extremely rare. Hypersensitivity reactions due to limited (1-2%) systemic absorption of iodine-based CM are very uncommon; however, patients with a history of such reactions should be managed as for intravascular iodine-based CM administration. For barium sulphate CM, nausea, vomiting, and constipation are the most reported adverse effects. Minor leakage into the mediastinum or aspiration of small amounts into the lungs is rarely life-threatening. In contrast, intraperitoneal leakage can trigger inflammatory reactions, granuloma formation, and intestinal adhesions. If bowel perforation is suspected, fluoroscopic examination with iodine-based CM should precede barium administration. Hypersensitivity may occur due to excipients within barium preparations rather than barium itself. KEY POINTS: Question What are the current safety issues associated with positive GI radiological CM? Finding Nausea and vomiting are the most commonly reported adverse effects of positive enteric CM. Many reports of other adverse effects date back to before 2000. Clinical relevance The use of positive GI CM has diminished in recent decades. However, these CM have excellent safety profiles and are safer than traditionally assumed.