Not just lower dose, but totally stop such a thing.
There is no scientific evidence of the human body containing in total more than about 20 mg of iodine. It is complete whackery to take, day after day, these gigantic amounts. There is not a single published medical reference advising it or showing data supporting it. In contrast, there are multiple large studies showing high iodine intake over prolonged time, but far far less amounts than this, causing reduced thyroid activity.
Consequences of excess iodine. Nat Rev Endocrinol. 2014 Mar; 10(3): 136-142.
More than adequate iodine intake may increase subclinical hypothyroidism and autoimmune thyroiditis. European Journal of Endocrinology (2011) 164 943-950
Iodine intake as a determinant of thyroid disorders in populations. Best Pract Res Clin Endocrinol Metab. 2010 Feb;24(1):13-27
Iodine toxicity from soy milk and seaweed ingestion is associated with serious thyroid dysfunction. Med J Aust. 2010 Oct 4;193(7):413-5.
Iodine Excess as an Environmental Risk Factor for Autoimmune Thyroid Disease. Int J Mol Sci. 2014 Jul; 15(7): 12895-12912.[/i]
Extreme iodine intake is supported only in the sense that all kinds of various crazy health ideas are advocated somewhere on the Web by someone, with various individual claims of "I benefited" but with nothing at all showing they wouldn't have benefited as much or more with far less amount or duration. They provide no evidence that they did not overshoot, no evidence that they did the best for themselves, nothing towards that being the best way or a harmless way to do it.
There's all kinds of things out there. This is one of them, and nothing more, except worse than many.
1 mg/day is plenty for ongoing and there's some evidence even that may be a little too much at least for some. This amount also will replenish within reasonable time: there are no giant stores that need replenishment, simply not true. If desired 2 mg/day for a short time such as a few weeks will replenish faster.