Ammonia N 13 and Breastfeeding

Summary of use during lactation

Information in this record refers to the use of ammonia N 13 as a diagnostic agent in PET scans. No information is available on the use of ammonia N 13 during breastfeeding. The Society for Nuclear Medicine and the International Commission on Radiological Protection states that breastfeeding need not be interrupted after administration of ammonia N 13,[1-3] although the manufacturer recommends withholding breastfeeding for 2 hours. This length of time is greater than 10 half-lives of the radioisotope, so the nursing infant should not be exposed to radiation if this the 2-hour time period is used. The mother can nurse just before administration of the radiopharmaceutical. 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.[4,5] Milk that is pumped by the mother during the time of breastfeeding interruption can either be discarded or stored and given to the infant after 10 physical half-lives, or about 2 hours, have elapsed. Nursing mothers should not work with radioactive substances used in PET scans in their workplace.[6]

Drug levels in milk and infant serum

Nitrogen N 13 decays by positron emission, emitting gamma photon with an energy of 511 keV. It has a physical half-life of 9.97 minutes.[3]

Effects in breastfed infants

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

Effects on lactation and breastmilk

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

References

1. Dorbala S, Di Carli MF, Delbeke D, et al. SNMMI/ASNC/SCCT guideline for cardiac SPECT/CT and PET/CT 1.0. J Nucl Med 2013;54:1485-507.23781013 PubMed
2. Mattsson S, Johansson L, Leide Svegborn S, et al. Radiation dose to patients from radiopharmaceuticals: A compendium of current information related to frequently used substances. ICRP Publication 128. Annex D. Recommendations on breast-feeding interruptions. Ann ICRP 2015;44 (2 Suppl):7-321.
3. Dilsizian V, Metter D, Palestro C, Zanzonico P. Advisory Committee on Medical Uses of Isotopes (ACMUI) Sub-Committee on Nursing Mother Guidelines for the Medical Administration of Radioactive Material. Final report submitted: January 31, 2019. 2019. https://www.nrc.gov/docs/ML1903/ML19038A498.pdf
4. Mountford PJ, Coakley AJ. A review of the secretion of radioactivity in human breast milk: Data, quantitative analysis and recommendations. Nucl Med Commun 1989;10:15-27.2645546 PubMed
5. Early PJ, Sodee DB. Principles and practice of nuclear medicine. 2nd ed. St Louis Mosby-Year Book, Inc 1995:1380-1.
6. Almén A, Mattsson S. Radiological protection of foetuses and breast-fed children of occupationally exposed women in nuclear medicine - Challenges for hospitals. Phys Med 2017;43:172-7.28882410 PubMed