I presume the mother is getting a lung scan.  Thus, she will likely get
technetium 99, which has a half life of six hours more or less.  Dr. Hale
says that the baby should be off the breast for up to three days, but I
disagree, because I don't think we must make sure that baby gets absolutely
*no* radioactivity.  As a pediatrician, I am aware that we do radioactive
isotope studies on babies all the time, and no one gets too excited about
it.

After about 6 hours, 1/2 the dose of the technetium will be gone from the
mother.  In another 6 hours 1/2 the remainder will be gone.  The blood
levels will drop quickly, and the baby can nurse much earlier than days
after the dose.  I would say that there is no need to stop at all.  I
realize not many agree with me, but that is my approach.  You want some
measure of decreased intake by the baby?  Stop 6 or 12 hours.  Two to three
days is too long.

Jack Newman, MD, FRCPC