Initially a wait and see approach - a fnbiopsy was done and showed benign so then it was checking on whether the nodule grew and whether my sub-clinical hyper was fluctating (it was). Antibody tests were negative.
Eventually the nodule grew to 3.4cm and I was becoming symptomatic - faster heartbeat, wired and tired, difficulty sleeping. Initially I was put on betablockers to keep the heartrate down, then given a choice to fix it by either surgery (partial thyroidectomy) or RAI (fine line in getting it exact enough to kill only the nodule without killing off the whole gland). That was when I furiously had to start researching to get the best option.
I initially chose the surgery and was given anti-thyroid meds so that I'd be euthyroid for the operation. They worked within weeks and I was comfortable enough to come off the betablockers. Then I changed my mind and went ahead with the RAI end of 2010, resulting in me being put on a low dose synthroid a year later, when I started heading hypo. I've been adjusting the doses since and am hopeful that I'll plateau comfortably soon; it appears my thyroid is definitely still supplementing by producing it's own hormone, so if that continues it will be a good outcome for me. (I'm currently taking 33mcg synthroid and hope not to have to go higher than 50, but time will tell - at present I get checked 6weeks to 3 monthly for my levels.
However everyone's story is a little different and every doctor's recommendation can be a little different too, so good luck with your research. I'm hoping your husbands is merely a transient condition, which, with anti-thyroid meds may rectify. Feel free to PM me anytime.
What did they do to fix your problem?
Start getting copies of all his blood tests so that you and he can monitor the condition yourselves as well.
My hyper was caused by a benign nodule that was overproducing hormone - which appears to be reasonably common among people who have been exposed to Radiation years before, and is somewhat higher in some areas of the Pacific Islands and post Chernobyl. This is not the most common cause of hyper, and scans would highlight, or, as Goolarra advised the TSI test would confirm Graves disease.
I'm sorry I can't answer re the iodine over-exposure alhough I do know that some cases of 'hyper' can be transient, so if their is neither Graves nor a nodule involved, it could be that medication and a watch and wait approach would be used (and the over-exposure further investigated). Hopefully you get some answers soon.
It is important to limit iodine intake when hyper. Your husband can ask his doctor to test his iodine levels to see if they are too high.
Has your husband had a TSI (thyroid stimulating immunoglobulin) test? TSI is the antibody marker for Graves' disease (autoimmune hyperthyroidism). Almost all hyperthyroidism is Graves' disease.