Editing Hyperthyroidism (section)

== Treatment ==

===Antithyroid drugs===
Thyrostatics ([[Antithyroid agent|antithyroid drugs]]) are drugs that inhibit the production of thyroid hormones, such as [[carbimazole]] (used in the UK) and [[methimazole]] (used in the US, Germany and Russia), and [[propylthiouracil]]. Thyrostatics are believed to work by inhibiting the [[iodination]] of [[thyroglobulin]] by [[thyroperoxidase]] and, thus, the formation of tetraiodothyronine (T<sub>4</sub>). Propylthiouracil also works outside the thyroid gland, preventing the conversion of (mostly inactive) T<sub>4</sub> to the active form T<sub>3</sub>. Because thyroid tissue usually contains a substantial reserve of thyroid hormone, thyrostatics can take weeks to become effective and the dose often needs to be carefully titrated over a period of months, with regular doctor visits and blood tests to monitor results.<ref name="Thyrotoxicosis and Hyperthyroidism"/>

===Beta-blockers===
Many of the common symptoms of hyperthyroidism such as palpitations, trembling, and anxiety are mediated by increases in beta-adrenergic receptors on cell surfaces. [[Beta blockers]], typically used to treat high blood pressure, are a class of drugs that offset this effect, reducing rapid pulse associated with the sensation of palpitations, and decreasing tremor and anxiety. Thus, a person with hyperthyroidism can often obtain immediate temporary relief until the hyperthyroidism can be characterized with the Radioiodine test noted above and more permanent treatment take place. Note that these drugs do not treat hyperthyroidism or any of its long-term effects if left untreated, but, rather, they treat or reduce only symptoms of the condition.<ref>{{Cite web|title=UpToDate|url=https://www.uptodate.com/contents/beta-blockers-in-the-treatment-of-hyperthyroidism|access-date=2021-05-17|website=www.uptodate.com}}</ref>

Some minimal effect on thyroid hormone production however also comes with [[propranolol]]—which has two roles in the treatment of hyperthyroidism, determined by the different isomers of propranolol. L-propranolol causes beta-blockade, thus treating the symptoms associated with hyperthyroidism such as tremor, palpitations, anxiety, and [[heat intolerance]]. D-propranolol inhibits thyroxine deiodinase, thereby blocking the conversion of T<sub>4</sub> to T<sub>3</sub>, providing some though minimal therapeutic effect. Other beta-blockers are used to treat only the symptoms associated with hyperthyroidism.<ref>{{cite journal | vauthors = Eber O, Buchinger W, Lindner W, Lind P, Rath M, Klima G, Langsteger W, Költringer P | title = The effect of D- versus L-propranolol in the treatment of hyperthyroidism | journal = Clinical Endocrinology | volume = 32 | issue = 3 | pages = 363–372 | date = March 1990 | pmid = 2344697 | doi = 10.1111/j.1365-2265.1990.tb00877.x | s2cid = 37948268 }}</ref> [[Propranolol]] in the UK, and [[metoprolol]] in the US, are most frequently used to augment treatment for people with hyperthyroid .<ref name=pmid1352658>{{cite journal | vauthors = Geffner DL, Hershman JM | title = Beta-adrenergic blockade for the treatment of hyperthyroidism | journal = The American Journal of Medicine | volume = 93 | issue = 1 | pages = 61–68 | date = July 1992 | pmid = 1352658 | doi = 10.1016/0002-9343(92)90681-Z }}</ref>

===Diet===
People with autoimmune hyperthyroidism (such as in [[Graves' disease|Grave's disease]]) should not eat foods high in iodine, such as [[edible seaweed]] and [[seafood]].<ref name=NIH2012/>

From a public health perspective, the general introduction of iodized salt in the United States in 1924 resulted in lower disease, goiters, as well as improving the lives of children whose mothers would not have eaten enough iodine during pregnancy which would have lowered the IQs of their children.<ref name=BI72213>{{cite news|title=How Adding Iodine To Salt Resulted in a Decade's Worth of IQ Gains for the United States|url=http://www.businessinsider.com/iodization-effect-on-iq-2013-7|access-date=23 July 2013|newspaper=Business Insider|date=22 July 2013| vauthors = Nisen M |url-status=live|archive-url=https://web.archive.org/web/20130723154256/http://www.businessinsider.com/iodization-effect-on-iq-2013-7|archive-date=23 July 2013}}</ref>

===Surgery===
[[Surgery]] ([[thyroidectomy]] to remove the whole thyroid or a part of it) is not extensively used because most common forms of hyperthyroidism are quite effectively treated by the radioactive iodine method, and because there is a risk of also removing the [[parathyroid glands]], and of cutting the [[recurrent laryngeal nerve]], making swallowing difficult, and even simply generalized [[staphylococcus|staphylococcal]] infection as with any major surgery. Some people with Graves' may opt for surgical intervention. This includes those that cannot tolerate medicines for one reason or another, people that are allergic to iodine, or people that refuse radioiodine.<ref>{{cite journal | vauthors = Catania A, Guaitoli E, Carbotta G, Bianchini M, Di Matteo FM, Carbotta S, Nardi M, Fabiani E, Grani G, D'Andrea V, Fumarola A | title = Total thyroidectomy for Graves' disease treatment | journal = La Clinica Terapeutica | volume = 164 | issue = 3 | pages = 193–196 | date = 2012 | pmid = 23868618 | doi = 10.7417/CT.2013.1548 }}</ref>

A 2019 [[systematic review]] concluded that the available evidence shows no difference between visually identifying the nerve or utilizing intraoperative [[neuroimaging]] during surgery, when trying to prevent injury to recurrent laryngeal nerve during thyroid surgery.<ref>{{Cite journal |last1=Cirocchi |first1=Roberto |last2=Arezzo |first2=Alberto |last3=D'Andrea |first3=Vito |last4=Abraha |first4=Iosief |last5=Popivanov |first5=Georgi I |last6=Avenia |first6=Nicola |last7=Gerardi |first7=Chiara |last8=Henry |first8=Brandon Michael |last9=Randolph |first9=Justus |last10=Barczyñski |first10=Marcin |date=2019-01-19 |editor-last=Cochrane Metabolic and Endocrine Disorders Group |title=Intraoperative neuromonitoring versus visual nerve identification for prevention of recurrent laryngeal nerve injury in adults undergoing thyroid surgery |journal=Cochrane Database of Systematic Reviews |volume=1 |issue=1 |pages=CD012483 |language=en |doi=10.1002/14651858.CD012483.pub2|pmid=30659577 |pmc=6353246 }}</ref>

If people have toxic nodules treatments typically include either removal or injection of the nodule with alcohol.<ref>{{cite book |title=Endocrinology : adult and pediatric|date=2010|publisher=Saunders/Elsevier|location=Philadelphia|isbn=978-1-4160-5583-9|page=Chapter 82|edition=6th|url=https://www.inkling.com/read/endocrinology-jameson-de-groot-6th/chapter-82/chapter082-reader-1 |url-access=subscription}}</ref>

===Radioiodine===
In [[iodine-131]] ([[radioiodine]]) [[Radiation therapy#Radioisotope and therapy (RIT)|radioisotope therapy]], which was first pioneered by Dr. [[Saul Hertz]],<ref name="Vignette">{{cite journal | vauthors = Hertz BE, Schuller KE | title = Saul Hertz, MD (1905-1950): a pioneer in the use of radioactive iodine | journal = Endocrine Practice | volume = 16 | issue = 4 | pages = 713–5 | date = 2010 | pmid = 20350908 | doi = 10.4158/EP10065.CO }}</ref> radioactive iodine-131 is given orally (either by pill or liquid) on a one-time basis, to severely restrict, or altogether destroy the function of a hyperactive thyroid gland. This isotope of radioactive iodine used for ablative treatment is more potent than diagnostic radioiodine (usually [[iodine-123]] or a very low amount of iodine-131), which has a biological half-life from 8–13 hours. Iodine-131, which also emits beta particles that are far more damaging to tissues at short range, has a half-life of approximately 8 days.  People not responding sufficiently to the first dose are sometimes given an additional radioiodine treatment, at a larger dose. Iodine-131 in this treatment is picked up by the active cells in the thyroid and destroys them, rendering the thyroid gland mostly or completely inactive.<ref name="Pmid">{{cite journal | vauthors = Metso S, Auvinen A, Huhtala H, Salmi J, Oksala H, Jaatinen P | title = Increased cancer incidence after radioiodine treatment for hyperthyroidism | journal = Cancer | volume = 109 | issue = 10 | pages = 1972–1979 | date = May 2007 | pmid = 17393376 | doi = 10.1002/cncr.22635 | s2cid = 19734123 | doi-access = free }}</ref>

Since iodine is picked up more readily (though not exclusively) by thyroid cells, and (more important) is picked up even more readily by over-active thyroid cells, the destruction is local, and there are no widespread side effects with this therapy. Radioiodine ablation has been used for over 50 years, and the only major reasons for not using it are pregnancy and breastfeeding ([[Breast|breast tissue]] also picks up and concentrates iodine). Once the thyroid function is reduced, replacement hormone therapy ([[levothyroxine]]) taken orally each day replaces the thyroid hormone that is normally produced by the body.<ref>{{cite web
 | work = AHFS Patient Medication Information
 | publisher = American Society of Health-System Pharmacists, Inc
 | title = levothyroxine
 | url = https://medlineplus.gov/druginfo/meds/a682461.html
 | access-date = 25 October 2021 }}</ref>

There is extensive experience, over many years, of the use of radioiodine in the treatment of thyroid overactivity and this experience does not indicate any increased risk of thyroid cancer following treatment. However, a study from 2007 has reported an increased number of cancer cases after radioiodine treatment for hyperthyroidism.<ref name="Pmid" />

The principal advantage of radioiodine treatment for hyperthyroidism is that it tends to have a much higher success rate than medications. Depending on the dose of radioiodine chosen, and the disease under treatment (Graves' vs. toxic goiter, vs. hot nodule etc.), the success rate in achieving definitive resolution of the hyperthyroidism may vary from 75 to 100%. A major expected side-effect of radioiodine in people with Graves' disease is the development of lifelong [[hypothyroidism]], requiring daily treatment with thyroid hormone. On occasion, some people may require more than one radioactive treatment, depending on the type of disease present, the size of the thyroid, and the initial dose administered.<ref>{{cite web |url=http://www.mythyroid.com/iodinehyper.html |title=Radioactive Iodine | date = 2005 | work = MyThyroid.com |access-date=2010-05-11 |url-status=dead |archive-url=https://web.archive.org/web/20100305000205/http://www.mythyroid.com/iodinehyper.html |archive-date=5 March 2010 }}</ref>

People with Graves' disease manifesting moderate or severe [[Graves' ophthalmopathy]] are cautioned against radioactive iodine-131 treatment, since it has been shown to exacerbate existing thyroid eye disease. People with mild or no ophthalmic symptoms can mitigate their risk with a concurrent six-week course of [[prednisone]]. The mechanisms proposed for this side effect involve a TSH receptor common to both [[thyroid epithelial cell|thyrocytes]] and retro-orbital tissue.<ref>{{cite journal | vauthors = Walsh JP, Dayan CM, Potts MJ | title = Radioiodine and thyroid eye disease | journal = BMJ | volume = 319 | issue = 7202 | pages = 68–69 | date = July 1999 | pmid = 10398607 | pmc = 1116221 | doi = 10.1136/bmj.319.7202.68 }}</ref>

As radioactive iodine treatment results in the destruction of thyroid tissue, there is often a transient period of several days to weeks when the symptoms of hyperthyroidism may actually worsen following radioactive iodine therapy. In general, this happens as a result of thyroid hormones being released into the blood following the radioactive iodine-mediated destruction of thyroid cells that contain thyroid hormone. In some people, treatment with medications such as [[beta blocker]]s ([[propranolol]], [[atenolol]], etc.) may be useful during this period of time. Most people do not experience any difficulty after the radioactive iodine treatment, usually given as a small pill. On occasion, neck tenderness or a sore throat may become apparent after a few days, if moderate inflammation in the thyroid develops and produces discomfort in the neck or throat area. This is usually transient, and not associated with a fever, etc.{{citation needed|date=August 2020}}

It is recommended that breastfeeding be stopped at least six weeks before radioactive iodine treatment and that it not be resumed, although it can be done in future pregnancies. It also shouldn't be done during pregnancy, and pregnancy should be put off until at least 6–12 months after treatment.<ref>{{Cite web |title=Radioactive Iodine Therapy: What is it, Treatment, Side Effects |url=https://my.clevelandclinic.org/health/treatments/16477-radioiodine-radioactive-iodine-therapy |access-date=2022-04-20 |website=Cleveland Clinic}}</ref><ref>{{Cite web |title=Radioactive Iodine |url=https://www.thyroid.org/radioactive-iodine/ |access-date=2022-04-20 |website=American Thyroid Association |language=en-US}}</ref>

A common outcome following radioiodine is a swing from hyperthyroidism to the easily treatable hypothyroidism, which occurs in 78% of those treated for Graves' thyrotoxicosis and in 40% of those with toxic multinodular goiter or solitary toxic adenoma.<ref name=pmid1710255>{{cite journal | vauthors = Berglund J, Christensen SB, Dymling JF, Hallengren B | title = The incidence of recurrence and hypothyroidism following treatment with antithyroid drugs, surgery or radioiodine in all patients with thyrotoxicosis in Malmö during the period 1970-1974 | journal = Journal of Internal Medicine | volume = 229 | issue = 5 | pages = 435–442 | date = May 1991 | pmid = 1710255 | doi = 10.1111/j.1365-2796.1991.tb00371.x | s2cid = 10510932 }}</ref> Use of higher doses of radioiodine reduces the number of cases of treatment failure, with penalty for higher response to treatment consisting mostly of higher rates of eventual hypothyroidism which requires hormone treatment for life.<ref name=pmid16390021>{{cite journal | vauthors = Esfahani AF, Kakhki VR, Fallahi B, Eftekhari M, Beiki D, Saghari M, Takavar A | title = Comparative evaluation of two fixed doses of 185 and 370 MBq 131I, for the treatment of Graves' disease resistant to antithyroid drugs | journal = Hellenic Journal of Nuclear Medicine | volume = 8 | issue = 3 | pages = 158–161 | year = 2005 | pmid = 16390021 }}</ref>

There is increased sensitivity to radioiodine therapy in thyroids appearing on [[Medical ultrasonography|ultrasound scans]] as more uniform (hypoechogenic), due to densely packed large cells, with 81% later becoming hypothyroid, compared to just 37% in those with more normal scan appearances (normoechogenic).<ref name=pmid17609305>{{cite journal | vauthors = Markovic V, Eterovic D | title = Thyroid echogenicity predicts outcome of radioiodine therapy in patients with Graves' disease | journal = The Journal of Clinical Endocrinology and Metabolism | volume = 92 | issue = 9 | pages = 3547–3552 | date = September 2007 | pmid = 17609305 | doi = 10.1210/jc.2007-0879 | doi-access = free }}</ref>

===Thyroid storm===
[[Thyroid storm]] presents with extreme symptoms of hyperthyroidism. It is treated aggressively with [[resuscitation]] measures along with a combination of the above modalities including: intravenous beta blockers such as [[propranolol]], followed by a [[thioamide]] such as [[methimazole]], an iodinated radiocontrast agent or an iodine solution if the radiocontrast agent is not available, and an intravenous [[steroid]] such as [[hydrocortisone]].<ref>{{cite book |title=Emergency Medicine: A Comprehensive Study Guide | edition = Sixth | vauthors = Tintinalli J |year=2004 |publisher=McGraw-Hill Professional |isbn=978-0-07-138875-7 |page=1312 }}</ref> [[Propylthiouracil]] is the preferred thioamide in thyroid storm as it can prevent the conversion of T4 to the more active T3 in the peripheral tissues in addition to inhibiting thyroid hormone production.<ref name="Lee 2023" />

=== Alternative medicine ===
In countries such as China, herbs used alone or with antithyroid medications are used to treat hyperthyroidism.<ref name=":0">{{cite journal | vauthors = Zen XX, Yuan Y, Liu Y, Wu TX, Han S | title = Chinese herbal medicines for hyperthyroidism | journal = The Cochrane Database of Systematic Reviews | issue = 2 | pages = CD005450 | date = April 2007 | volume = 2007 | pmid = 17443591 | pmc = 6544778 | doi = 10.1002/14651858.CD005450.pub2 }}</ref> Very low quality evidence suggests that [[Chinese herbology|traditional Chinese herbal medications]] may be beneficial when taken along with routine hyperthyroid medications, however, there is no reliable evidence to determine the effectiveness of Chinese herbal medications for treating hyperthyroidism.<ref name=":0" />