The Editorial Executive Committee welcomes letters, which should be less than 250 words. Before a decision to publish is made, letters which refer to a published article may be sent to the author for a response. Any letter may be sent to an expert for comment. When letters are published, they are usually accompanied in the same issue by their responses or comments. The Committee screens out discourteous, inaccurate or libellous statements. The letters are sub-edited before publication. Authors are required to declare any conflicts of interest. The Committee's decision on publication is final.
Letter to the Editor
Editor, – I would like to commend Kenneth Thomson and Dinesh Varma for their succinct discussion of the safety profile of iodinated radiographic contrast media (Aust Prescr 2010;33:19-22).
However a noticeable absence in the article is the discussion of oral contrast – particularly the increasing use of injectable iodinated radiographic contrast media as oral contrast (after dilution) for abdominal CT.
One of the issues related to iodinated media like iohexol or diatrizoate sodium is the alleged cumulative nephrotoxicity of these media when given orally in addition to the intravenous dose. This perception appears to be in error. From what I can tell, iohexol is poorly absorbed in the intact gastrointestinal tract and about 1% of the dose is excreted by the kidney. There is however a theoretical potential to cause renal dysfunction in a dehydrated patient as the hypertonic oral iodinated media can cause excessive excretion of water into the gastrointestinal lumen, precipitating a body fluid loss into the third space.
I would appreciate it if the authors can comment on this as the use of oral iodinated media is becoming more common in Australia, replacing the cheaper but less palatable barium meal.
Locum orthopaedic registrar