Is Iothalamate Sodium I 125 safe while breastfeeding?

Here is what LactMed, the Drugs and Lactation Database published by the U.S. National Institute of Child Health and Human Development (NICHD), reports about Iothalamate Sodium I 125. The text below is quoted from that source — it is not our own verdict.

Summary of use during breastfeeding

Information in this record refers to the use of iothalamate sodium I 125 as a kidney function diagnostic agent. No information is available on the use of iothalamate sodium I 125 during breastfeeding. However, the biologic half-life of iothalamate after intravenous administration is 1.5 hours with normal kidney function, so the drug will be almost completely eliminated from the body in 8 hours. This time may be longer in patients with impaired kidney function and in patients who receive the drug by subcutaneous injection.[1] If the mother has expressed and saved milk prior to the examination, she can feed it to the infant during the period of nursing interruption.[2-4]

Mothers concerned about the level of radioactivity in their milk could ask to have it tested at a nuclear medicine facility at their hospital. When the radioactivity is at background levels, they may safely resume breastfeeding. A method for measuring milk radioactivity and determining the time when a mother can safely resume breastfeeding has been published.[5]

Effects on the breastfed infant

Relevant published information was not found as of the revision date.

Effects on milk supply

Relevant published information was not found as of the revision date.

Levels in milk

I 125 is a low-energy pure gamma emitter with a physical half-life of 59.4 days.[6]

Alternatives LactMed lists

Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Iothalamate Sodium I 125” (LM1136). LactMed on NCBI Bookshelf. LactMed is a registered trademark of the U.S. Department of Health and Human Services.

Educational summary of an authoritative source — not medical advice. Never start, stop, or change a medicine while breastfeeding without confirming with your doctor.