Is Sodium Pertechnetate Tc 99m 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 Sodium Pertechnetate Tc 99m. 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 sodium pertechnetate Tc 99m as a diagnostic agent. A US Nuclear Regulatory Commission subcommittee has recommended that nursing be discontinued for 24 hours after administration of all technetium Tc 99m diagnostic products to simplify guidance recommendations, although this time interval may be longer than necessary.[1] However, other international agencies recommend shorter times for low doses (see table). During the period of interruption, the breasts should be emptied regularly and completely. 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.[2,3] The milk that is pumped by the mother during the time of breastfeeding interruption can either be discarded or stored refrigerated frozen and given to the infant after 10 physical half-lives, or about 60 hours, have elapsed. Mothers need not refrain from close contact with their infants after usual clinical doses.[3]
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 a safe level, she may resume breastfeeding. A method for measuring milk radioactivity and determining the time when a mother can safely resume breastfeeding has been published.[4]
For nursing mothers who work with Tc 99m substances in their workplace, there is no need to take any precautions other than those appropriate for general radiation protection.[5]
Dose | Duration of Interruption 1110 MBq (30mCi) | 48 hours[6] 440 MBq (12 mCi) | 12 hours[7] 185 MBq (5 mCi) | 4 to 12 hours[4,7]
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
Tc 99m is a gamma emitter with a principal photon energy of 140 keV and a physical half-life of 6.04 hours. With perchlorate blocking, the effective half-life of Tc 99m averages 5.2 hours and 0.82% of an administered dose appears in breastmilk. Without blocking, the effective half-life is 3.4 hours and 10% of an administered dose appears in breastmilk.[1]
Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Sodium Pertechnetate Tc 99m” (LM685). 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.