I thought there was only so much someone could recieve I'm not sure if it is a measured amount or the number of doses.
Hi, Summer... there used to be a suggested 'artificial ceiling' on doses a few years ago, which some doctors adhered to, that was around the neighbourhood of 1000 mCi's in a liftetime.
But this is truly an 'artificial' figure, really, and many doctors wouldn't have any concern, whatsoever with going over this amount in a lifetime, providing they were relatively confident that the radioactive iodine treatments were continuing to work.
So, it wouldn't matter if someone had doses of 150mCi's or 200 mCi's repeatedly over and over, 5 or even 10 or more times over the years; as long as it continued, each time, to be 'soaked up' by the offending tissues, it could be repeated again, over and over, as long as those tissues kept 'responding' by sucking it up.
Of course, in most cases, we want the tissues to be very tiny - 'debulked' surgically, then have the remaining cells treated with the RAI. Time wise, it is suggested that we do not have treatment doses more frequently than 6 months to a year; some nuc med experts believe that each dose continues to 'work' on a cellular level, killing off the abherant tissue, for many months after an RAI treatment dose... even up to a year.
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