This recently published study from my laboratories shows that levels of Mesalamine (5-Aminosalicylic acid) in human milk are exceedingly low. Despite the dose, the relative infant doses in these 10 moms (RID) were all lower than 0.1%. Good news, moms can safely use these products for ulcerative colitis and Crohn's disease.
A six year old boy with severe asthma, which was not responding to treatment, was found to be allergic to secondhand marijuana smoke. He had daily symptoms of cough, shortness of breath and wheezing. It was discovered that some family members had started smoking marijuana in the house, although never in the same room as the boy.
This is an excellent article that reviews the current knowledge about the use of various iodinated and gadoliniium-containing radio contrast agents used in CT and MRI scans. While the iodinated compounds are probably safe to use in breastfeeding mothers, there is some concern over the "repeated" use of the metal-containing gadoliniium products used for MRI scans. Excellent review of this subject. TWH