Editing Hyperthyroidism (section)

==Signs and symptoms==
Hyperthyroidism may be asymptomatic or present with significant symptoms.<ref name=Clin2014/> Some of the symptoms of hyperthyroidism include nervousness, irritability, increased perspiration, heart racing, hand tremors, anxiety, [[insomnia|trouble sleeping]], thinning of the skin, fine brittle hair, and muscular weakness—especially in the upper arms and thighs. More frequent bowel movements may occur, and diarrhea is common. Weight loss, sometimes significant, may occur despite a good appetite (though 10% of people with a hyperactive thyroid experience weight gain), vomiting may occur, and, for women, menstrual flow may lighten and menstrual periods may occur less often, or with longer cycles than usual.<ref>{{cite journal | vauthors = Koutras DA | title = Disturbances of menstruation in thyroid disease | journal = Annals of the New York Academy of Sciences | volume = 816 | issue = 1 Adolescent Gy | pages = 280–284 | date = June 1997 | pmid = 9238278 | doi = 10.1111/j.1749-6632.1997.tb52152.x | s2cid = 5840966 | bibcode = 1997NYASA.816..280K }}</ref><ref>{{cite book | vauthors = Shahid MA, Ashraf MA, Sharma S | chapter = Physiology, Thyroid Hormone |  title = StatPearls [Internet] | location = Treasure Island (FL) | publisher = StatPearls Publishing| date = January 2021 | pmid = 29763182 }}</ref>
[[File:Proptosis and lid retraction from Graves' Disease.jpg|left|thumb|[[Exophthalmos]] seen in [[Graves' ophthalmopathy|Graves’ ophthalmopathy]]]]
Thyroid hormone is critical to normal function of cells. In excess, it both overstimulates [[metabolism]] and disrupts the normal functioning of [[sympathetic nervous system]], causing "speeding up" of various body systems and symptoms resembling an overdose of [[epinephrine]] (adrenaline). These include fast heartbeat and symptoms of [[palpitation]]s, nervous system [[tremor]] such as of the hands and [[anxiety (mood)|anxiety]] symptoms, digestive system [[hypermotility]], unintended weight loss, and, in [[lipid panel]] blood tests, a lower and sometimes unusually low serum [[cholesterol]].<ref name="Thyrotoxicosis and Hyperthyroidism">{{cite web |url= https://www.lecturio.com/concepts/thyrotoxicosis-and-hyperthyroidism/| title= Thyrotoxicosis and Hyperthyroidism
|website=The Lecturio Medical Concept Library |access-date= 7 August 2021}}</ref>

Major clinical signs of hyperthyroidism include [[weight loss]] (often accompanied by an increased [[appetite]]), anxiety, [[heat intolerance]], hair loss (especially of the outer third of the eyebrows), muscle aches, weakness, fatigue, hyperactivity, irritability, [[hyperglycemia|high blood sugar]],<ref name="Thyrotoxicosis and Hyperthyroidism"/> [[polyuria|excessive urination]], [[polydipsia|excessive thirst]], [[delirium]], [[tremor]], [[pretibial myxedema]] (in [[Graves' disease]]), [[emotional lability]], and sweating.  [[Panic attacks]], inability to concentrate, and [[memory]] problems may also occur. [[Psychosis]] and [[paranoia]], common during [[thyroid storm]], are rare with milder hyperthyroidism. Many persons will experience complete remission of symptoms 1 to 2 months after a [[euthyroid]] state is obtained, with a marked reduction in anxiety, sense of exhaustion, irritability, and depression. Some individuals may have an increased rate of anxiety or persistence of [[affective]] and cognitive symptoms for several months to up to 10 years after a euthyroid state is established.<ref>{{cite book|title=Bradley's neurology in clinical practice.|publisher=Elsevier/Saunders|location=Philadelphia, PA|chapter=Depression and Psychosis in Neurological Practice.|year=2012|isbn=978-1-4377-0434-1|pages=102–103|edition=6th}}</ref> In addition, those with hyperthyroidism may present with a variety of physical symptoms such as [[palpitations]] and [[Heart arrhythmia|abnormal heart rhythms]] (the notable ones being [[atrial fibrillation]]), shortness of breath ([[dyspnea]]), loss of [[libido]], [[amenorrhea]], [[nausea]], [[vomiting]], [[diarrhea]], [[gynecomastia]] and [[feminization (biology)|feminization]].<ref>{{cite journal | vauthors = Chan WB, Yeung VT, Chow CC, So WY, Cockram CS | title = Gynaecomastia as a presenting feature of thyrotoxicosis | journal = Postgraduate Medical Journal | volume = 75 | issue = 882 | pages = 229–231 | date = April 1999 | pmid = 10715765 | pmc = 1741202 | doi = 10.1136/pgmj.75.882.229 }}</ref> Long term untreated hyperthyroidism can lead to [[osteoporosis]]. These classical symptoms may not be present often in the elderly.<ref>{{Cite web |title=Hyperthyroidism - Symptoms and causes |url=https://www.mayoclinic.org/diseases-conditions/hyperthyroidism/symptoms-causes/syc-20373659 |access-date=2024-06-28 |website=Mayo Clinic |language=en}}</ref>

Bone loss, which is associated with overt but not subclinical hyperthyroidism, may occur in 10 to 20% of patients. This may be due to an increase in bone remodelling and a decrease in bone density, and increases fracture risk. It is more common in postmenopausal women; less so in younger women, and men. Bone disease related to hyperthyroidism was first described by Frederick von Recklinghausen, in 1891; he described the bones of a woman who died of hyperthyroidism as appearing "worm-eaten".<ref>{{cite web | last=Miragaya | first=Joanna | title=Preventing 'Worm-eaten Bones' From Hyperthyroidism | website=Medscape | date=31 July 2023 | url=https://www.medscape.com/viewarticle/994801}}</ref>

Neurological manifestations can include [[tremor]]s, [[Chorea (disease)|chorea]], [[myopathy]], and in some susceptible individuals (in particular of Asian descent) [[Thyrotoxic periodic paralysis|periodic paralysis]]. An association between thyroid disease and [[myasthenia gravis]] has been recognized. Thyroid disease, in this condition, is [[autoimmune]] in nature and approximately 5% of people with myasthenia gravis also have hyperthyroidism. Myasthenia gravis rarely improves after thyroid treatment and the relationship between the two entities is becoming better understood over the past 15 years.<ref name="pmid16840920">{{cite journal | vauthors = Trabelsi L, Charfi N, Triki C, Mnif M, Rekik N, Mhiri C, Abid M | title = [Myasthenia gravis and hyperthyroidism: two cases] | language = French | journal = Annales d'Endocrinologie | volume = 67 | issue = 3 | pages = 265–9 | date = June 2006 | pmid = 16840920 | doi = 10.1016/s0003-4266(06)72597-5 }}</ref><ref>{{cite journal |first1=Rong-hua |last1=Song |first2=Qiu-ming |last2=Yao |first3=Bin |last3=Wang |first4=Qian |last4=Li |first5=Xi |last5=Jia |first6=Jin-an |last6=Zhang |title=Thyroid disorders in patients with myasthenia gravis: A systematic review and meta-analysis |journal=Autoimmunity Reviews |issue=10 |date=October 2019 |volume=18 |doi=10.1016/j.autrev.2019.102368 |pmid=31404702 |s2cid=199549144 |url=https://doi.org/10.1016/j.autrev.2019.102368 |access-date=2024-01-22|url-access=subscription }}</ref><ref>{{cite journal |vauthors=Zhu Y, Wang B, Hao Y, Zhu R |title=Clinical features of myasthenia gravis with neurological and systemic autoimmune diseases |journal=Front Immunol |date=September 2023 |volume=14 |issue=14:1223322 |doi=10.3389/fimmu.2023.1223322 |doi-access=free |pmid=37781409 |pmc= 10538566}} </ref>[[File:Blausen 0534 Goiter.png|thumb|Illustration depicting enlarged thyroid that may be associated with hyperthyroidism|255x255px]]In [[Graves' disease]], [[ophthalmopathy]] may cause the eyes to look enlarged because the eye muscles swell and push the eye forward. Sometimes, one or both eyes may bulge. Some have swelling of the front of the neck from an enlarged thyroid gland (a goiter).<ref name="next.thyroid.org">{{cite web |url=http://next.thyroid.org/patients/patient_brochures/hyperthyroidism.html |title=Hyperthyroidism | publisher = American Thyroid Association |access-date=2010-05-10 |url-status=dead |archive-url=https://web.archive.org/web/20110305123450/http://next.thyroid.org/patients/patient_brochures/hyperthyroidism.html |archive-date=5 March 2011}}</ref>

Minor ocular (eye) signs, which may be present in any type of hyperthyroidism, are eyelid retraction ("stare"), [[extraocular muscles|extraocular muscle]] weakness, and [[Lid lag|lid-lag]].<ref>{{Cite book| vauthors = Mehtap C |url=http://worldcat.org/oclc/472720688|title=Differential diagnosis of hyperthyroidism|publisher=Nova Science Publishers|year=2010|isbn=978-1-61668-242-2|pages=xii|oclc=472720688}}</ref> In hyperthyroid ''stare'' ([[Dalrymple sign]]) the eyelids are retracted upward more than normal (the normal position is at the superior [[Corneal limbus|corneoscleral limbus]], where the "white" of the eye begins at the upper border of the iris). Extraocular muscle weakness may present with double vision. In lid-lag ([[von Graefe's sign]]), when the person tracks an object downward with their eyes, the eyelid fails to follow the downward moving iris, and the same type of upper globe exposure which is seen with lid retraction occurs, temporarily. These signs disappear with treatment of the hyperthyroidism.{{Citation needed|date=December 2010}}

Neither of these ocular signs should be confused with [[exophthalmos]] (protrusion of the eyeball), which occurs specifically and uniquely in hyperthyroidism caused by Graves' disease (note that not all exophthalmos is caused by Graves' disease, but when present with hyperthyroidism is diagnostic of Graves' disease). This forward protrusion of the eyes is due to immune-mediated inflammation in the retro-orbital (eye socket) fat. Exophthalmos, when present, may exacerbate hyperthyroid lid-lag and stare.<ref>{{cite web|author=Faculty of Medicine & Dentistry |title=Course-Based Physical Examination – Endocrinology – Endocrinology Objectives (Thyroid Exam) |url=http://www.med.ualberta.ca/education/ugme/clinicaled12/clinskills_endocrinology.cfm?yr=1 |work=Undergraduate Medical Education |year=2006 |publisher=University of Alberta |access-date=28 January 2007 |url-status=dead |archive-url=https://web.archive.org/web/20080119214105/http://www.med.ualberta.ca/education/ugme/clinicaled12/clinskills_endocrinology.cfm?yr=1 |archive-date=19 January 2008}}</ref>

===Thyroid storm===
{{main|Thyroid storm}}

Thyroid storm is a severe form of thyrotoxicosis characterized by rapid and often [[cardiac arrhythmia|irregular heart beat]], high temperature, vomiting, diarrhea, and mental agitation. Symptoms may not be typical in the young, old, or pregnant.<ref name=Clin2014/> It usually occurs due to untreated hyperthyroidism and can be provoked by infections.<ref name=Clin2014/> It is a [[medical emergency]] and requires hospital care to control the symptoms rapidly. The mortality rate in thyroid storm is 3.6-17%, usually due to multi-organ system failure.<ref name="Lee 2023" />

===Hypothyroidism===
Hyperthyroidism due to certain types of [[Hashimoto's thyroiditis|thyroiditis]] can eventually lead to [[hypothyroidism]] (a ''lack'' of thyroid hormone), as the thyroid gland is damaged. Also, [[radioiodine]] treatment of Graves' disease often eventually leads to hypothyroidism. Such hypothyroidism may be diagnosed with thyroid hormone testing and treated by oral thyroid hormone supplementation.<ref>{{Cite web|title=Hypothyroidism - Diagnosis and treatment - Mayo Clinic|url=https://www.mayoclinic.org/diseases-conditions/hypothyroidism/diagnosis-treatment/drc-20350289|access-date=2021-05-06|website=www.mayoclinic.org}}</ref>