Lugol is a pre-operative preparation for thyreotoxicosis in order to condense tissue, this facilitates to easy approach of the operation, as in thyrotoxicosis gland is very loose and, the risk of bleeding is high, and the role of lugol is to prevent from bleedeng

Effect of lugol in toxic goitre is controversial. However the radio-active iodine is reported to irradiates and destroys most of the thyroid cells thereby reducing the production of thyroid hormones in toxic goitre, And about 50% of patients become euthyroid in one year.

Lugol solution is used to prepare patients with Graves disease because its increased vascular condition, which it is not the same  as in toxic multinodular goiter. This has been known since ancient times, so that there is not a place for giving Lugol solution in the last condition and,. Lugol solution may worsen the thyrotoxicosis of multinodular goiter.

@Ozoda Azimova yes, it reduces vascularity but do you use it for toxic MNG? It is used as preoperative preparation for Grave's disease.. My question is - is it effective in toxic MNG. If not, then why?

In Graves disease  there is a huge increase in vascularity (demonstrated by ultrasound as "hell" or inferno), which  does not occur in multinodular goiter, and that phenomena decreases with Lugol solution, making  thyroidectomy safer, which to my knowledge,  has not been demonstrated in a controled study with multinodular goiter.

Dear Fernando Bolanos, Lugol's solution can also be used to achieve rapid control of severe thyrotoxicosis before thyroidectomy, right? In this situation, why will it not work for toxic MNG? Any explanation? Thank you

Yes, I think that, in toxic multinodular goiter (not multinodular goiter without thyroxicosis), Lugol solution added to other drugs (antithyroid drugs and propranolol among others), may be used to control thyrotoxicosis, but not by itself to prepare patients to surgery. I think that if used without other drugs may precipitate Jod Basedow thyrotoxicosis

Lack of escape to Wolff Chaikof phenomena with the development of hypothyroidism after administration of Lugol solution has been reported in Graves disease treated with radioactive iodine and Hashimoto's thyroiditis, but not in untreated toxic multinodular goiter.

Sorry, Cheah Sin Dee. I do not know any study to answer your question, but I would not give it to control thyrotoxicosis in those patients without adding antithyroid drugs.

Dear Fernando Bolanos, thank you for the explanation provided. Appreciated it.

In toxic MNG, the uptake of iodine is differ from nodule to nodule, therefore it is not very effective for RAI and also for pre-op preparation.

In relationship to the first instance, it is not useful to give elemental before radioactive iodine because the amount of radioactive iodine uptake decreases afterward

In relation to its preoperative use in a multinodular goiter, I would say I would advise it after I see prospective random studies demonstrating its usefulness.(A classical sentence of the dean of my hospital)

why not make us encounter the Jod–Basedow effect in TSH independent patients?

why u assume just the Wolff–Chaikoff effect only ?

I saw a patient with Jod Basedow disease recently. He was 80-year-old, sent by an internal medicine doctor, was taking a large amount of iodine as vitamins and minerals tablets. Interestingly, the clinical picture was of a large weight loss (15Kg. in two months) and a decrease of lower extremity muscle strength. The TSH was inhibited and the free thyroxine increased, with normal total thyroxine. Interestingñy, de thyroid uptake was very low, as described in the classical book "The Thyroid" by Dr.Werner. I prescribed a low MMZ dose and he has been improving clinically, and the TSH level increased after one-month treatment from 0.05 to 0,.1mUI/L. Also, patient the heart rate was normal.