Originally Posted by geekgolightly
it depends on whether or not they are using contrast medium like iodine.
i do not know about the uptake of free ions from this medium, but this research contradicts what i know about most radioactive product.....
kellymom.com (a reputable AP/breastfeeding website) has other information:http://www.kellymom.com/health/meds/radioisotopes.html
Use of Radioisotopes (and other imaging agents) during Lactation
* Radiocontrast dyes
Radiocontrast dyes (contrast media used with x-rays)
X-rays, MRIs, CAT scans, Intravenous Pyelogram (IVP), ultrasound, mammograms, etc. do not affect breastfeeding. Barium is sometimes used as a contrast agent; it is not absorbed orally and thus does not affect breastfeeding.
Sometimes radiocontrast dyes are used to aid the imaging - these dyes do not require that mom interrupt breastfeeding.
"Although most package inserts for these products suggest that nursing mothers postpone breastfeeding their babies for 24 hours after use, research indicates that this is not necessary (Kubik-Huch 2000; Rofsky 1993; Nielson 1987; Fitz-John 1982). In Medications and Mothers' Milk (2002), Dr. Thomas Hale explains that 'Although under usual circumstances iodine products are contraindicated in nursing mothers (due to ion trapping in milk), these products are unique in that they are extremely inert and do not release free iodine... They are virtually unabsorbed after oral administration' (Hale, p. 480). In mothers who have used these agents while breastfeeding, no effects have been reported in their nursing babies (Kubik-Huch 2000; Nielson 1987). These preparations are also used in children for diagnostic purposes."
source: Mohrbacher N, Stock J. The Breastfeeding Answer Book, Third Revised Edition. Schaumburg, Illinois: La Leche League International, 2003, p. 508.
"Contrast medium is not appreciably deionated. In addition, the absorption of hydrophilic contrast medium is minimal when it is given orally for imaging studies of the gastrointestinal tract. Since no toxicity is known in full-term infants even after the direct administration of contrast medium, the use of these compounds by breastfeeding women appear to pose no risk to their infants."
source: Ito S. Drug therapy for breast-feeding women (Review). N Engl J Med 2000 Jul 13;343(2):118-26. (see particularly "Iodine-Containing Contrast Medium and Antiseptic Agents" on p. 123-124.)