Radioactive iodine shrinks thyroid nodules as part of a treatment for hyperfunctioning thyroid nodules and goiters with more than one nodule. However, pregnant women and women who are trying to have children should not have radioactive iodine, as stated by Cleveland Clinic.
Thyroid nodules are anomalous growths of thyroid cells within the larger gland. The thyroid sits on the front of the neck just beneath the larynx. Several different reasons cause the growth of thyroid tissue, leading to the formation of nodules. One is the formation of cancer, but cancerous nodules comprise less than 5 percent of the total. The most common causes of nodules are genetic predisposition and iodine deficiency, according to Cleveland Clinic.
When nodules are not cancerous, treatment is not always necessary. Frequent checkups are necessary to monitor the nodules for changes into cancerous tissue. Some physicians use levothyroxine, a synthetic thyroid hormone, to treat the nodules along the line of thinking that the drug tells the pituitary gland to make less of a different thyroid hormone necessary for tissue growth. The end goal of levothyroxine treatment is to shrink the nodules, but research is still undetermined as to the effectiveness of this treatment, as of 2015, notes Cleveland Clinic.