Your trip sounds MARVELOUS!!!!! Are you from the U.S? Or Europe?
I do not recall if you are on thyroid hormone replacement now, when you had your RAI. I am assuming you can get your RX for 90 days. If you are going to be gone longer than three months, tell this to your pharmacy provider. Explain the situation to them, ask if you can have the one time exception (it is usually once a year) to have your insurance plan cover having your drug for the time you will be gone (and add a couple weeks to that, to provide for the unexpected.)
I did this when I went to China and Tibet, and they did grant it. That is BY FAR the easiest way to manage this. If you are going to be gone 3 months or less, but the timing of the refill is wrong, explain that to them. They should be fine with refilling it early. I was on Synthroid, and did not want to mess with any of this in foreign countries. And even in English speaking ones, you would probably get a generic, and if you are on one thyroid hormone, it is better not to switch to another one.
I suggest the following:
1. Go to travel medicine, get the shots they require or suggest. You need them. we are still the same person, even with Graves'. It's like, but not the same, as having high blood pressure that is controlled with meds. You have high blood pressure without the meds. But when taking the meds, you don't have high blood pressure. Thyroid hormone is something our body produces naturally. We are replacing it, cause our bodies let us down in this area.
2. Explore travel insurance carefully. Generally, it is for a crisis situation,injury, stroke, heart attack, unforeseen accident of some kind.
Travel insurance is tricky. If you are young and healthy, I suggest exploring the student travel services regarding travel insurance for good information.
3. Take your own supplies of tylenol, ibuprofen, benedryl cream and pills,
band aides. And LOMOTIL! (for travelers' diarrhea.( I am sure I am forgetting some stuff. I went to travel medicine at the Univ. of Washington. Any university is very familiar with what you should take, what you need. They are dealing with people from other countries, and us traveling internationally all the time.
4. Labs, blood work. The best thing to do is have labs before you leave. Unless you find yourself in a real health situation with Graves', which is probably unlikely, given that you are planning this trip. Consult with your endo on this. Think of all the problems we have communicating with our OWN docs, not to mention someone speaking Mandarin. Kinda depends if you will be on/off the beaten path.
5. Vaccinations and shots. I would not neglect them. YOu need'em.
6. Hotter climates? Just like anyone else, I'm thinking. Drink safe water and plenty of water. Stuff you already know.
Medicine in China probably pretty good, with English speakers available. Depends on where you are. Same with India. Same with Isatanbul, Turkey, my favorite country of all of them! Love Turkey! Super healthy food there.
Hope this give you some beginning thoughts!
I am so happy for you to do this trip!!
TED 2008-present. OD for pressure on optic nerve 02/02/10
Eye muscle surgery 09/23/10 Upper eyelid surgery 02/01/11
Lower eyelids with grafts from palate, 10/5, 10/25/11
Graves dx/thyroidectomy 1959-Synthroid from 1980