Iodine is part of a cycle of nutrients which balance out the hormonal system-
-selenium, which protects the thyroid when iodine is used in creating hydrogen peroxide (cleaning the blood on it's way to the brain)
-Zinc, producing glutathione peroxidase and carrying out heavy metals
-B2 and B3 (proper function of iodine receptors on the cell walls, dilating bloodvessels so iodine can penetrate further into the tissues, producing AT (energy))
-magnesium (producing energy, allowing enzymes to function properly, helping remove heavy metals)
-Sodium chloride (salt!) (creating hydrogen peroxide, which is what you need for breaking down goitre tissues!, shunting out bromide)
-Vitamin C (cofactor to almost every nutrient you can think of!)
Many of the accounts of goitre reduction are from folk who balanced out their iodine with the co-nutrients, and used months on it finding out just what balance they needed to use (by tracking how they felt and what they needed).
Some had really specific needs, like Wombat gave us great articles on Vitamin A for stopping breast pain, endometriosis and overactive menses. Boron (a halide which displaces flouride, another antagonist of iodine), B1 (sulfur, another vital one for creating hydrogen peroxide), B12, methionine are other nutrients which folk have found incredibly helpful on their journey.
Yeah, your goitre is likely to see reduction with iodine, but you do need to be careful to monitor the progress over a longer period, and be prepared to balance it with helper nutrients to prevent problems and speed your progress. Knowledge is power, so keep praying for guidance and the right steps to take. :-)
Assuming a 2% Lugol's solution at 6 drops per day, makes a 15mg/day dose. Headaches are a sign of the iodine starting to displace material that doesn't belong in the system- and/or breaking down tissues which are due for the recycling bin (iodine induces cellular apoptosis, cell death, when a cell reaches the end of it's lifespan or does not express the right genes.)
I'd say maintain your dosage where you are, research the conutrients and salt loading (make certain you are getting in magnesium when salt loading), and test what your system needs so you can continue your progress.
The Iodine VWT team forum is for folk wanting support when adding in all the conutrients, and the forum regulars there are experts in iodine megadosing (100+ mg)
The other Iodine Forum s also use co-nutrients, but reccommend the method you and your ND have been using, which is called titration (slow ramping up).
One of the best places to find the co-nutrients and helpful literature is breastcancerchoices.org (in their store).