After treatment with radioactive iodine, you may develop hypothyroidism (too little thyroid hormone).

The first phase is typically hyperthyroidism; the thyroid then either returns to normal, or a woman develops hypothyroidism.

Of children treated with radiation therapy, most develop hypothyroidism within the first 2 to 5 years posttreatment, but new cases can occur later.

Some women develop hypothyroidism after pregnancy (often referred to as "postpartum thyroiditis").

Some patients develop hypothyroidism only a few months after treatment while others may not be affected for 20-30 years.

And most people who receive radioactive iodine eventually develop hypothyroidism (having too little thyroid hormone).

If you develop hypothyroidism, you will need to take thyroid hormone medicine for the rest of your life.

After treatment, many people develop hypothyroidism (too little thyroid hormone).

Also, people who test positive for antithyroid antibodies may never develop hypothyroidism.

Then, the thyroid either returns to normal or a woman develops hypothyroidism.