I have Graves, and, like Baba, I also felt considerable frustration with the delay in the meds taking effect. In my case, I was grounded for about 8 months before my thyroid finally got back to normal. I'm currently still on the pills; my doctor is recommending the radioactive iodine treatment, but I'm putting it off. The iodine treatment is kind of "horseshoes and hand-grenades" in that it is not extremely precise. The objective is to kill off part, but not all of the gland. The lucky ones no longer have to take any meds, the others might need a small dose of one or the other, depending on whether the iodine treatment was a little too much or too little. I can't speak for the Euro authorities, but from the FAA's standpoint, the disease is not too serious; as long as the blood test shows the thyroid function is within the normal range and there are no side effect to the meds, then you're good to go. According to my AME, the FAA does not object to a one time treatment with the radioactive iodine, but if the condition requires continued doses of radiation, then the medical certificate would be suspended until the treatment is complete. Do some web surfing and you'll find lots of horror stories about the radiation treatment, and a very wide range of "alternative" treatments; there are those who believe the entire medical profession are quacks, and prefer to self-medicate with large quantites of "natural supplements" rather than take one pill prescribed by the establishment. On the one hand, the thyroid treatment uses a much smaller dosage of radiation than, say, cancer treatment. It's an outpatient procedure, with mild nausea being the only immediate side effect. On the other hand, radiation in any dose is serious stuff, and should not be undertaken lightly.