Hypothyroidism presents with the following signs and symptoms:

Cardiovascular

The heart muscle slows down and contractility decreases therefore the cardiac output is also decreased. Bradycardia, decreased systolic and increased diastolic blood pressure, systemic hypotension and in some severe cases, pericardial effusion may occur.

Urogenital

In females, menstrual abnormalities occur like amenorrhea and dysmenorrhea. Fertility is impaired.

Musculoskeletal

There is lethargy and generalised muscular and joint pain. Weakness of upper and lower extremities is also sometimes found. There is pitting or non pitting edema in extremities.

Nervous

Headaches, paresthesia and forgetfulness are common. Impaired memory, altered mental status and depression may occur in severe cases.

Gastrointestinal

Intestinal and gastric stasis, constipation and decreased appetite are common symptoms.

Eye

Blurred vision due to periorbital edema and puffing may occur.

Others

Hair turns coarse and brittle, skin becomes dry and pale, alopecia, weight gain, and cold intolerance and sleepiness are common presentations.

Complications are rare but may include infertility, fatal pericardial effusion and sudden hypotension leading to shock.

• Weight Gain

  Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold Too little thyroid hormone. Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold. [icd9data.com]

  Here we describe a 3-year-old Caucasian girl who was admitted to our Clinic due to pericardial effusion, muscle weakness and weight gain. [ncbi.nlm.nih.gov]

• Fatigue

  BACKGROUND Muscular symptoms, including stiffness, myalgia, cramps, and fatigue, are present in the majority of the patients with symptomatic hypothyroidism, but rhabdomyolysis, the rapid breakdown of skeletal muscle, is a rare manifestation. [ncbi.nlm.nih.gov]

  Adrenal Fatigue and Hypothyroidism The following table outlines the key differences in the signs and symptoms between Adrenal Fatigue and hypothyroidism symptoms. [drlam.com]

  On admission, he endorsed persistent dysarthria, generalized fatigue and improvement in extremity weakness. General examination was notable for bradycardia and lack of edema. [neurology.org]

  This may lead to a variety of symptoms, including weight gain, fatigue, depression, dry skin, brain fog, cold intolerance, muscle cramps, and constipation. [verywellhealth.com]

• Goiter

  Intra-amniotic levothyroxine (L-T4) administration was performed, and the fetal goiter decreased in size. A female infant was delivered without goiter and complications. Thyroid function was within the normal range. [ncbi.nlm.nih.gov]

• Weakness

  Within a week, he developed intermittent weakness of his left hand followed by intermittent weakness of both legs. On admission, he endorsed persistent dysarthria, generalized fatigue and improvement in extremity weakness. [neurology.org]

  Here we describe a 3-year-old Caucasian girl who was admitted to our Clinic due to pericardial effusion, muscle weakness and weight gain. [ncbi.nlm.nih.gov]

  If carpal tunnel progresses, hand muscles may waste away leading to weakness, particularly decreased grip strength. [verywellhealth.com]

  Weakness and aches are normal following strenuous activity. However, new, and especially increasing, weakness or aching is a good reason to make an appointment with your physician. [healthline.com]

• Anemia

  Haematopoietic system: mild anemia, the bone marrow is hypo plastic and the plasma and RBC turnover is decreased. Pernicious anemia, megaloblastic anemia (due to folic acid deficiency), some patients may present with leukopenia. [flexikon.doccheck.com]

  MATERIALS AND METHODS: Patients with toxic nodular goiter and heart failure with concomitant anemia were included. Patients underwent treatment with radioiodine before the planned heart transplant or pacemaker implantation (combined ICD/CRT-D). [ncbi.nlm.nih.gov]

  […] present, usually normocytic-normochromic and of unknown etiology, but it may be hypochromic because of menorrhagia and sometimes macrocytic because of associated pernicious anemia or decreased absorption of folate. [smartypance.com]

  Anemia A deficiency of thyroid hormone impairs the production of red blood cells in your bone marrow, the spongy tissue that lies in the center of certain bones. [verywellhealth.com]

  Chronic nephritis hypothyroidism due to water and sodium retention performance for the skin pale, edema, anemia, high blood pressure and blood cholesterol, and some patients are also associated with urine protein positive, so often thought to be kidney [tongshantang.net]

• Hoarseness

  Hypothyroidism symptomatology was similar in both groups, except for a greater frequency of hoarseness in the group with HAH. Migraine history was more frequent in the patients with HAH (53% vs 38%, p [ncbi.nlm.nih.gov]

  (adolescent hypothyroidism) symptoms: Slow growth Delayed tooth development Tiredness Feeling cold Constipation Slow growth Delayed puberty Hoarse voice Slow speech Droopy eyelids Puffy and swollen face Hair loss Dry skin Slow pulse Weight gain (modest [stanfordchildrens.org]

• Dyspnea

  Respiratory: Bradypnea, diminished vital capacity and total lung capacity, dyspnea Abdominal: Hypoactive bowel sounds and abdominal bloating MSK: Swollen hands, swollen feet and leg edema NEURO: Dementia, paranoid ideation, slow delayed reflexes and cerebellar [uth.tmc.edu]

  Respiratory System: the patients with hypothyroidism may present with dyspnea, obstructive sleep apnea and frequent respiratory infections. [flexikon.doccheck.com]

  Myxedema crisis, the extreme of symptomatic hypothyroidism, is life-threatening and includes vital sign abnormalities such as bradycardia, diastolic hypertension, hypothermia and symptoms such as edema, dyspnea, and altered mental status including psychosis [clinicaladvisor.com]

  The location of a goiter and the dynamics of its growth determine whether, and how, it will produce symptoms: Retrosternal goiter often causes dysphagia, while retrotracheal goiter often causes dyspnea ( 4 ). [dx.doi.org]

• Common Cold

  Causes of this problem include: The immune system attacking the thyroid gland Viral infections (common cold) or other respiratory infections Pregnancy (often called postpartum thyroiditis) Other causes of hypothyroidism include: Certain medicines, such [nlm.nih.gov]

• Bradypnea

  Respiratory: Bradypnea, diminished vital capacity and total lung capacity, dyspnea Abdominal: Hypoactive bowel sounds and abdominal bloating MSK: Swollen hands, swollen feet and leg edema NEURO: Dementia, paranoid ideation, slow delayed reflexes and cerebellar [uth.tmc.edu]

• Constipation

  Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold Too little thyroid hormone. Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold. [icd9data.com]

  She was admitted to the tertiary care setup with the complains of cold intolerance, numbness in the limbs, high blood pressure & constipation, patient also had complain of weight gain, lab revealed high TSH, low Free thyroid hormones & positive anti thyroglobulin [ncbi.nlm.nih.gov]

  While constipation is a common complaint in patients with hypothyroidism, it's uncommon for constipation to be the only or most severe symptom ( 24 ). [healthline.com]

  Feeling tired Dry skin Constipation Weight gain Slow heart rate Slow growth Not starting puberty Periods that aren't regular Acquired hypothyroidism is easily treated by taking medicine every day called Levothyroxine. [cincinnatichildrens.org]

• Nausea

  A 42-year-old hypothyroid shepherd presented with a progressive abdominal lump accompanied by nausea and abdominal fullness. In addition, he had worsening hypothyroidism, despite supranormal doses of thyroxine. [ncbi.nlm.nih.gov]

  Side effects Common side effects may include: - anxiety - nervousness - depressive condition - insomnia - headache - dizziness During the first week of drug use the patient may also experience the following side effects: stomachache, nausea, diarrhea, [corpohs.com]

  Rarely, hyperthyroidism in pregnancy is caused by hyperemesis gravidarum—severe nausea and vomiting that can lead to weight loss and dehydration. [web.archive.org]

  Rarely, hyperthyroidism in pregnancy is linked to hyperemesis gravidarum —severe nausea and vomiting that can lead to weight loss and dehydration. Experts believe this severe nausea and vomiting is caused by high levels of hCG early in pregnancy. [niddk.nih.gov]

• Dysphagia

  Disease features include low grade fever, thyroid pain, dysphagia, and elevated erythrocyte sedimentation rate (ESR). The disease is usually self-limited and does not normally result in longstanding thyroid dysfunction. [emedicine.com]

• Failure to Thrive

  If symptoms are present they may include: Jaundice (yellow skin and whites of the eyes) Frequent choking A large, protruding tongue A puffy face Difficulty feeding Failure to thrive and develop normally Constipation Poor muscle tone Excessive sleepiness [southerncross.co.nz]

  Hypothyroidism Clinical features of congenital hypothyroidism include: Hypotonia and lethargy Feeding difficulties, resulting in poor weight gain and failure to thrive Constipation Hoarse cry with reduced frequency of crying Puffy appearance; large head [dermnetnz.org]

  Infants and children may present more often with lethargy and failure to thrive. Women who have hypothyroidism may present with menstrual irregularities and infertility. In older patients, cognitive decline may be the sole manifestation. [web.archive.org]

  Crossref, Medline, Google Scholar 528 Stein MT, Kessler DB, Hubbard E 2004 Failure to thrive in a four-month-old nursing infant. J Dev Behav Pediatr 25 : S69–S73. [doi.org]

• Loss of Appetite

  […] of appetite Constipation See 'Signs and Symptoms of Hypothyroidism' for full list. [thyroiduk.org.uk]

  You should also contact your doctor if any of these symptoms develop for the first time while you’re taking antithyroid medicines: increased tiredness or weakness loss of appetite skin rash or itching easy bruising If you are allergic to or have severe [niddk.nih.gov]

  From the age of 20 – 30 however, a growing incidence of anxiety and depression is found, with symptoms such as withdrawal, mutism, psychomotoric retardation, subdued moods, passivity, loss of appetite and sleeping disorders ( 11 ). [tidsskriftet.no]

• Heart Failure

  The increased value of the index of distribution of red blood cells volume (RDW) may be a prognostic marker in patients diagnosed with chronic heart failure (CHF). Hypothyroid patients present higher RDW values if compared to healthy controls. [ncbi.nlm.nih.gov]

  Patients were divided into two groups: those with heart failure and those without heart failure. [endocrinenews.endocrine.org]

• Palpitations

  A 33 year-old, 8-week pregnant woman with hypothyroidism, presents with a 2-week history of palpitations, sweating, nervousness and fatigue. Physical examination shows tachycardia (108 bpm), distal tremors and diffuse goiter. [ncbi.nlm.nih.gov]

  While you are taking thyroid replacement therapy, tell your doctor if you have any symptoms that suggest your dose is too high, such as: Palpitations Rapid weight loss Restlessness or shakiness Sweating In most cases, thyroid hormone level becomes normal [nlm.nih.gov]

  […] organs and systems in your body that these hormones interact with start to speed up, creating symptoms such as: Weight loss Difficulty concentrating Feeling hot and sweating Problems falling asleep Anxiety, nervousness and irritability Racing heart and palpitations [geisinger.org]

• Hearing Impairment

  Hearing impairment in CH is of considerable interest. [ncbi.nlm.nih.gov]

• Dry Skin

  Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold Too little thyroid hormone. Symptoms include weight gain, constipation, dry skin, and sensitivity to the cold. [icd9data.com]

  Feeling tired Dry skin Constipation Weight gain Slow heart rate Slow growth Not starting puberty Periods that aren't regular Acquired hypothyroidism is easily treated by taking medicine every day called Levothyroxine. [cincinnatichildrens.org]

  Myxedema is more specific to thyroid problems than other causes of dry skin ( 16 ). Summary: Hypothyroidism commonly causes dry skin. However, most people with dry skin do not have hypothyroidism. [healthline.com]

  It involves slowing of body functions, and symptoms include weight gain, dry skin, constipation, cold intolerance, puffy skin, hair loss, fatigue, and menstrual irregularity in women. [labtestsonline.org]

• Sweating

  A 33 year-old, 8-week pregnant woman with hypothyroidism, presents with a 2-week history of palpitations, sweating, nervousness and fatigue. Physical examination shows tachycardia (108 bpm), distal tremors and diffuse goiter. [ncbi.nlm.nih.gov]

  They may include Fatigue Weight gain A puffy face Cold intolerance Joint and muscle pain Constipation Dry skin Dry, thinning hair Decreased sweating Heavy or irregular menstrual periods and fertility problems Depression Slowed heart rate To diagnose hypothyroidism [medlineplus.gov]

  While you are taking thyroid replacement therapy, tell your doctor if you have any symptoms that suggest your dose is too high, such as: Palpitations Rapid weight loss Restlessness or shakiness Sweating In most cases, thyroid hormone level becomes normal [nlm.nih.gov]

  As a result, the organs and systems in your body that these hormones interact with start to speed up, creating symptoms such as: Weight loss Difficulty concentrating Feeling hot and sweating Problems falling asleep Anxiety, nervousness and irritability [geisinger.org]

• Alopecia

  Bilaterally symmetric alopecia, with the exception of pinnal involvement, does not appear to develop, but focal areas of alopecia over the craniolateral carpi, caudal hocks, and dorsal and lateral tailbase have occasionally been observed. [web.archive.org]

  Bilaterally symmetric alopecia, except for pinnal involvement, does not appear to develop, but focal areas of alopecia over the craniolateral carpi, caudal hocks, and dorsal and lateral tailbase have occasionally been seen. [merckmanuals.com]

  Alopecia, weight gain, mental dullness, fatigue, cold intolerance, infertility and neurological deficits are seen. In food animals the syndrome is classical neonatal colloid goiter. [medical-dictionary.thefreedictionary.com]

  Others Hair turns coarse and brittle, skin becomes dry and pale, alopecia, weight gain, and cold intolerance and sleepiness are common presentations. [symptoma.com]

• Decreased Sweating

  They may include Fatigue Weight gain A puffy face Cold intolerance Joint and muscle pain Constipation Dry skin Dry, thinning hair Decreased sweating Heavy or irregular menstrual periods and fertility problems Depression Slowed heart rate To diagnose hypothyroidism [medlineplus.gov]

  Some common symptoms of hypothyroidism include fatigue weight gain a puffy face trouble tolerating cold joint and muscle pain constipation dry skin dry, thinning hair decreased sweating heavy or irregular menstrual periods fertility problems depression [niddk.nih.gov]

  sweating Swelling of the hands, face, and eyelids (called edema) "Brain Fog" Another symptom commonly described in connection with hypothyroidism is "brain fog." [verywellhealth.com]

  Some common symptoms of hypothyroidism are fatigue weight gain a puffy face cold intolerance joint and muscle pain constipation dry skin dry, thinning hair decreased sweating heavy or irregular menstrual periods and impaired fertility depression slowed [web.archive.org]

• Pruritus

  […] the recommended initial dose of # mg/m#/day, the most commonly reported adverse reactions to Targretin were hyperlipaemia ((primarily elevated triglycerides) # %), hypothyroidism (# %), hypercholesterolaemia (# %), headache (# %), leucopenia (# %), pruritus [et.glosbe.com]

  Occasionally, secondary pyoderma (which may produce pruritus) is observed. In moderate to severe cases, thickening of the skin occurs secondary to accumulation of glycosaminoglycans (mostly hyaluronic acid) in the dermis. [web.archive.org]

  Occasionally, secondary pyoderma (which may produce pruritus) is seen. In moderate to severe cases, thickening of the skin occurs secondary to accumulation of glycosaminoglycans (mostly hyaluronic acid) in the dermis. [merckmanuals.com]

  Pruritus and dysesthesia. In: Dermatology. 3rd ed. Philadelphia, Pa.: Saunders Elsevier; 2012. . Accessed July 27, 2016. Goldsmith LA, et al., eds. Atopic dermatitis. In: Fitzpatrick's Dermatology in General Medicine. 8th ed. [mayoclinic.org]

  In medical terminology, itching is known as pruritus. Generalized itch that occurs all over the body is often more difficult to treat than localized itch. [medicinenet.com]

• Periorbital Edema

  During physical exam, pay particular attention to the following: General: Weight gain and bradycardia HEENT: Dull expression, swollen face, periorbital edema, decreased auditory acuity, swollen tongue, hoarseness, enlarged thyroid gland (goiter), glandular [uth.tmc.edu]

  edema Pleural and pericardial effusion Table 2. [web.archive.org]

  Other signs of hypothyroidism include periorbital edema, dry skin and prolonged relaxation phase of deep tendon reflexes. [clinicaladvisor.com]

  Eye Blurred vision due to periorbital edema and puffing may occur. Others Hair turns coarse and brittle, skin becomes dry and pale, alopecia, weight gain, and cold intolerance and sleepiness are common presentations. [symptoma.com]

• Blurred Vision

  vision Decreased hearing Fullness in the throat, hoarseness Hashimoto thyroiditis is difficult to distinguish clinically, but the following symptoms are more specific to this condition: Feeling of fullness in the throat Painless thyroid enlargement Exhaustion [emedicine.medscape.com]

  Eye Blurred vision due to periorbital edema and puffing may occur. Others Hair turns coarse and brittle, skin becomes dry and pale, alopecia, weight gain, and cold intolerance and sleepiness are common presentations. [symptoma.com]

• Muscle Cramp

  This may lead to a variety of symptoms, including weight gain, fatigue, depression, dry skin, brain fog, cold intolerance, muscle cramps, and constipation. [verywellhealth.com]

  You may experience symptoms such as: Fatigue Forgetfulness Dry skin, dry hair and brittle nails Slowing of your bowels or constipation Weight gain Muscle cramps Reduced menstrual flow Depression The most common cause of hypothyroidism is an autoimmune [geisinger.org]

  cramps Dry skin Goiter (swelling of thyroid gland) Brittle nails Slow heart rate Irregular period Sensitivity to cold Constipation Carpal tunnel syndrome Treatment for hypothyroidism Levothyroxine sodium tablets (aka Synthroid) can be taken once a day [piedmont.org]

  Common symptoms and signs include: Fatigue Depression Modest weight gain Cold intolerance Excessive sleepiness Dry, coarse hair Hair loss Menstrual disturbances Mood changes Decreased perspiration Constipation Dry skin Muscle cramps Increased cholesterol [medicinenet.com]

• Muscle Weakness

  Here we describe a 3-year-old Caucasian girl who was admitted to our Clinic due to pericardial effusion, muscle weakness and weight gain. [ncbi.nlm.nih.gov]

  People with hypothyroidism-induced myopathy often complain of muscle pain and stiffness, along with proximal muscle weakness that can make simple activities like rising from a chair, climbing stairs, or washing hair difficult. [verywellhealth.com]

  These include: sluggishness depression dry skin or hair loss feeling cold muscle weakness poor memory or trouble concentrating constipation facial puffiness weight gain (even when not eating more or exercising less) slowed growth slow sexual development [kidshealth.org]

  weakness Weight loss Lighter, less frequent menstrual periods Lack of energy and fatigue “The symptoms can be variable and non-specific, so the only way to definitively diagnose a thyroid condition is with a simple blood test,” says Papaleontiou, a member [healthblog.uofmhealth.org]

  Muscle weakness. Muscle aches, cramps, tenderness, or stiffness. Increased sensitivity to cold. Constipation. Pale, dry skin. Puffy face. Hoarse voice. Elevatedblood Joint pain, stiffness, or swelling. [familydoctor.org]

• Myalgia

  BACKGROUND Muscular symptoms, including stiffness, myalgia, cramps, and fatigue, are present in the majority of the patients with symptomatic hypothyroidism, but rhabdomyolysis, the rapid breakdown of skeletal muscle, is a rare manifestation. [ncbi.nlm.nih.gov]

  Common Symptoms of Hypothyroidism Arthralgias Cold intolerance* Constipation Depression Difficulty concentrating Dry skin Fatigue* Hair thinning/hair loss Memory impairment Menorrhagia Myalgias Weakness Weight gain Table 1. [web.archive.org]

  Dry skin, constipation, headaches, arthralgia, myalgia, paresthesia, and menorrhagia may also occur. [clinicaladvisor.com]

  Cerebellar ataxia Delayed relaxation of deep tendon reflexes Cognitive/ psychiatric Reduced attention span Memory deficits Depression Cardiovascular Bradycardia Diastolic hypertension Pericardial effusion Decreased exercise tolerance Musculoskeletal Myalgias [racgp.org.au]

• Arthralgia

  Musculoskeletal system: muscle stiffness, weakness, cramps, mialgias, arthralgias, joint stiffness and effusions, Carpal Tunnel syndrome and delayed linear bone growth in children. [flexikon.doccheck.com]

  Common Symptoms of Hypothyroidism Arthralgias Cold intolerance* Constipation Depression Difficulty concentrating Dry skin Fatigue* Hair thinning/hair loss Memory impairment Menorrhagia Myalgias Weakness Weight gain Table 1. [web.archive.org]

  Dry skin, constipation, headaches, arthralgia, myalgia, paresthesia, and menorrhagia may also occur. [clinicaladvisor.com]

  Musculoskeletal symptoms (especially arthralgias) occur often, but arthritis is rare. Muscular aches and weakness, often mimicking polymyalgia rheumatica or polymyositis, and an elevated CK level may occur. [merckmanuals.com]

  Musculoskeletal symptoms (especially arthralgias) occur often, but arthritis is rare. Muscular aches and weakness, often mimicking polymyalgia rheumatica or polymyositis, and an elevated creatine kinase (CK) level may occur. [msdmanuals.com]

• Mood Swings

  Symptoms of hypothyroidism aren’t always apparent but may include: Cold intolerance Fatigue Dry skin Forgetfulness Constipation Depressive mood swings In contrast, hyperthyroidism causes the body’s processes to speed up and functions quicken, leading [healthblog.uofmhealth.org]

• Loss of Libido

  […] of libido recurrent urinary and respiratory tract infections anemia depression If left untreated, the following symptoms can manifest: hoarseness puffiness in the face thinned or missing eyebrows slow heart rate hearing loss If it develops in children [medicalnewstoday.com]

  There are many signs and symptoms of an underactive thyroid the main ones being: Weight gain Slow movements, thought and speech Pins and needles Breathlessness Dizziness Palpitations Loss of libido Dry/gritty eyes Hoarse voice Difficulty swallowing Hair [thyroiduk.org.uk]

• Lethargy

  A 75-year-old man experienced neurologic symptoms including memory impairment, ataxic gait, sensory polyneuropathy and myopathy, lethargy, and edema of the face and lower extremities. [ncbi.nlm.nih.gov]

  In its most severe form, there is accumulation of mucopolysaccharides in the skin and edema, known as myxedema Deficiency of thyroid gland activity; characterized by decreased basal metabolic rate, fatigue and lethargy, sensitivity to cold, and menstrual [icd9data.com]

  The course can develop rapidly; lethargy progresses to stupor and then coma. [web.archive.org]

  This is a rare and potentially fatal form of the disease where the symptoms can include enlarged tongue, swollen face, hoarseness and extreme lethargy, which may progress to a coma. [southerncross.co.nz]

• Slow Speech

  speech Droopy eyelids Puffy and swollen face Hair loss Dry skin Slow pulse Weight gain (modest, no more than 5-10 lbs) The symptoms of hypothyroidism may resemble other conditions or medical problems. [stanfordchildrens.org]

  Here are the most common symptoms and signs: Dull facial expressions Tiredness and lack of energy (fatigue) Not being able to handle cold Hoarse voice Slow speech Droopy eyelids Puffy and swollen face Weight gain Constipation Sparse, coarse, and dry hair [uclahealth.org]

  It is diagnosed by clinical features such as a typical facial appearance, hoarse slow speech, and dry skin and by low levels of thyroid hormones. Management includes treatment of the cause and administration of thyroxine. [merckmanuals.com]

• Difficulty Concentrating

  Symptoms associated with hypothyroidism include: Fatigue Lack of energy or drive Daytime sleepiness Weight gain Water retention or bloating (also known as myxedema) Thinning hair Dry skin Constipation Difficulty concentrating It is very important to keep [columbiasurgery.org]

  As a result, the organs and systems in your body that these hormones interact with start to speed up, creating symptoms such as: Weight loss Difficulty concentrating Feeling hot and sweating Problems falling asleep Anxiety, nervousness and irritability [geisinger.org]

  You should contact your doctor if your child experiences difficulty falling asleep or restless sleep or difficulty concentrating in school. These may be signs that your current thyroid hormone dose may be too high and you are being over treated. [healthychildren.org]

  concentrating Feeling cold when others feel hot Noticing hair that is coarse and dry, breaking, brittle, or falling out Noticing skin that is coarse, dry, scaly, and thick, especially the soles of your feet An unusually low pulse or blood pressure Slow [verywellhealth.com]

• Tingling

  The symptoms of hypothyroidism usually develop slowly over a number of years and include: Fatigue Numbness and tingling in hands Constipation Weight gain Intolerance to cold Dry, coarse skin and hair Decreased sexual interest Frequent, heavy menstrual [my.clevelandclinic.org]

  Symptoms of carpal tunnel syndrome may begin with burning and tingling in the palm of the hand and fingers, especially the thumb, index finger, and middle finger. [verywellhealth.com]

  […] signs: Dull facial expressions Tiredness and lack of energy (fatigue) Not being able to handle cold Hoarse voice Slow speech Droopy eyelids Puffy and swollen face Weight gain Constipation Sparse, coarse, and dry hair Coarse, dry, and thickened skin Hand tingling [uclahealth.org]

• Paresthesia

  Neurologic and Psychiatric manifestations: Headache, vertigo, Paresthesias, Carpal Tunnel Syndrome, delayed relaxation of deep tendon reflexes (intention tremor, nystagmus), cognitive deficits, depression and dementia. [flexikon.doccheck.com]

  Dry skin, constipation, headaches, arthralgia, myalgia, paresthesia, and menorrhagia may also occur. [clinicaladvisor.com]

  Metabolic manifestations: Cold intolerance, modest weight gain (due to fluid retention and decreased metabolism), hypothermia Neurologic manifestations: Forgetfulness, paresthesias of the hands and feet (often due to carpal tunnel syndrome caused by deposition [merckmanuals.com]

  Sleepiness Muscle pain, joint pain, weakness in the extremities Depression Emotional lability, mental impairment Forgetfulness, impaired memory, inability to concentrate Constipation Menstrual disturbances, impaired fertility Decreased perspiration Paresthesias [emedicine.medscape.com]

A complete work up includes checking of functional hormone levels of first T3 and T4 to see if the hypothyroidism is primary. Then levels of TSH and TRH are examined to determine any secondary causes. The plasma levels of Anti-TPO antibodies are also evaluated to check for Hashimoto’s [5].

• Hyponatremia

  This review will focus on the thyroid and its link with serum hyponatremia, and review the available literature on the topic. [doi.org]

  Mental status changes including lethargy, cognitive dysfunction, and even psychosis, and hypothermia are the hallmark features of myxedema coma. 33 Hyponatremia, hypoventilation, and bradycardia can also occur. [web.archive.org]

  Thyroid panel (TSH, Free T4)- Overt hypothyroidism will demonstrate an increase in TSH and a decrease in T3 and T4 levels Subclinical hypothyroidism may show an increased but normal level of TSH with normal levels of free T4 CBC for anemia Electrolytes (hyponatremia [uth.tmc.edu]

  Hyponatremia is often present so care when administering fluids is needed to avoid worsening that state. [clinicaladvisor.com]

• Hypertriglyceridemia

  Fenofibrate is a fibric acid derivative indicated for use in hypertriglyceridemia and mixed dyslipidemia treatment among adults. [ncbi.nlm.nih.gov]

Primary hypothyroidism can be treated by treating the cause. Nutritional deficiency can be corrected by adjusting an adequate intake of Iodine in diet [7]. Systemic manifestations can be treated by giving Levothyroxine (LT4) between 50-75 micrograms daily for mild to moderate hypothyroidism [6]. Effects are usually seen within 3-6 days of treatment.

Myxoedema is treated by giving a 200-250 microgram dose intravenously at first and then levelled down to about 50 microgram/day, accompanied by intravenous glucocorticoids.

Initial Stage

Initially, there is a gradual decrease in hormone levels causing low metabolism. This results in features like lethargy, easy fatiguability, weight gain, bradycardia and hypotension. Then there is pitting edema in lower extremities, especially around the ankles, coarse brittle hair, skin pallor and dryness [9]. A goitre may develop.

Advanced Stage

In advanced stage of this condition, the goiter may become enlarged and sometimes toxic and nodular. There may be severe hypotension and massive weight gain, slow speech and movements, hyporeflexia, myxadematous nonpitting edema, pericardial effusion, periorbital swelling and infertility.

The etiology of hypothyroidism can be broadly divided into primary, secondary and tertiary. Each category has various factors that predispose towards hypothyroidism.

Primary Hypothyroidism

This category consists of all such causes that deter the synthesis and/or secretion of thyroid hormones from the thyroid gland. It includes:

• Iodine deficiency hypothyroidism
• Iodine excess hypothyroidism 
• Chronic lymphocytic thyroiditis
• Sub acute thyroiditis
• Drug induced or iatrogenic hypothyroidism 
• Postpartum thyroiditis

Iodine Deficiency Hypothyroidism

The most common cause of primary hypothyroidism worldwide is Iodine deficiency. Iodine is one of the basic building blocks of thyroid hormones. Required for the synthesis of T3 and T4, Iodine deficiency leads to hypertrophy and hyperplasia of the follicular cells creating a goitre.

Iodine Excess Hypothyroidism

An overload of Iodine causes a gradual inhibition of iodide organification occurring in the thyroid follicles. This effect, called the Wolff-Chiakoff effect can occur due to very high levels of Iodine in the blood caused by some radio contrast dyes, drugs like amiodarone, increased intake of seafood and seaweed, etc. the Wolff-Chiakoff effect is however, short lived due to the rapid down regulation by the sodium-iodide symporter[10].

Chronic Lymphocytic Hypothyroidism

This is an autoimmune condition and commonly known as Hashimoto's disease. In this disease, thyroid antigens are mistakenly taken as foreign by the immune system which then launches a full scale attack on thyroid follicles. The attacking antibodies cause a chronic immune response that leads to a build-up of a lymphocytic infiltrate and progressive damage and destruction of the gland parenchyma.
Circulating anti-thyroid peroxidase antibodies (Anti-TPO) are the hallmark of this disease.
Hashimoto's disease is the most common acquired cause of hypothyroidism in the United States as well as other countries where there is a normal intake of Iodine.

Sub acute Thyroiditis

Sub acute granulomatous thyroiditis is an uncommon, self-limiting disorder that usually affects middle aged females. It is a painful form of thyroiditis associated with viral infections leading to an increased ESR, fever and dysphagia. This disease is also known as Quatrain Disease.

Drug Induced or Iatrogenic Hypothyroidism

Many drugs are known to cause hypothyroidism if used for a prolonged period of time [1]. The most common drugs predisposing to hypothyroidism include:

• Amiodarone
• Lithium
• Stavudine
• Ethionamide
• Interferon Alpha
• Thalidomide
• Phenobarbital
• Rifampin
• Carbamazepine
• Para-amino salicylic acid
• Phenytoin

Iatrogenic causes may include the use of radioactive iodine for the treatment of Grave's disease and exposure to radiation as part of treatment of cancers such as neck neoplasms, Hodgkin's lymphoma, salivary gland tumours, etc. Patients who have undergone thyroid lobectomy, which may or may not be accompanied with isthmectomy, have a 12-30% chance of developing hypothyroidism.

Postpartum Thyroiditis

After 2 months to about a year from delivery, about 10% women may develop thyroid insufficiency. This condition is usually transient and can be avoided and treated with levothyroxine but in some cases it may cause permanent hypothyroidism. Chances of developing postpartum thyroiditis is increased to about 25% in females with diabetes mellitus type I.

Secondary and Tertiary Hypothyroidism

The factors involved in this category are directly or indirectly involved in modifying the function of the thyroid gland. They include:

• TSH deficiency
• TRH deficiency or resistance
• Sheehan syndrome
• Pituitary and Hypothalamic tumours
• Congenital non-goiterous hypothyroidism 
• Drugs
• Radiation damaging the hypothalamic-pituitary axis

TSH Deficiency

A deficiency in the Thyroid Stimulating Hormone secreted by the pituitary gland may cause improper functioning of the thyroid gland and decreased synthesis of T3 and T4 [4].

TRH Deficiency or Resistance

A deficiency in the hypothalamic Thyroid Releasing Hormone may cause none to low secretion of TSH from the pituitary gland and therefore, decreased production of thyroid hormones. TRH deficiency may arise due to an isolated mutation in the TRH gene, inherited in an autosomal recessive fashion. A defect in the TRH receptors on the pituitary, due to a mutation in the THRH gene, produces TRH resistance and it also gives the same results. TRH resistance is a very rare autosomal recessive disease.

Sheehan Syndrome

Sheehan syndrome, a postpartum complication in which pituitary cells are infarcted due to increased blood loss during delivery may lead to decreased production of TSH and therefore, T3 and T4.

Pituitary and Hypothalamic Tumours

Tumours in or around these two glands may impinge on and suppress the function of hormone secreting cells causing hypothyroidism.

Congenital Non-Goiterous Hypothyroidism Type 4

This autosomal recessive disease results in low TSH levels which remain low despite injecting TRH [3]. It is caused by a mutation in the TSHB gene.

Drugs and Radiation

Continuous use of some drugs like prednisone and dopamine as well as exposure to direct radiation may damage the hypothalamic-pituitary axis causing hypothyroidism, among other systemic manifestations.

Hypothyroidism occurs worldwide.

Sex

It is more common in females, the female-to-male ratio being 10:1

Race

It is more prevalent in Caucasians than in Hispanics or Blacks.

Age

Hypothyroidism affects people of all ages. Primary hypothyroidism can occur at any age but a higher prevalence is found in patient over 65 years.

Under normal conditions the thyroid gland releases around 100-125 nmol of T4 daily of which most is converted in the peripheral tissues into T3, the active form of the hormone. This conversion from prohormone to active hormone is due to 5' deiodination.
The active hormone, T3 now circulates in the blood and acts on various receptors causing a wide range of systemic and metabolic effects.

Due to an infection, glandular loss, autoimmune attack or iodine deficiency, or due to any other cause mentioned above, the synthesis of T4 is impaired. Decreased production and secretion of T4 leads to decreased levels of T3 in blood which is unable to act on all its receptors, producing systemic manifestations.

Effects of hypothyroidism include decreased heart contractility and cardiac output, increased insulin resistance, increased cholesterol levels particularly those of LDL. Effects in the gastrointestinal tract include achloroydia, decreased metabolic rate leading to gastric stasis, prolonged intestinal transit time and weight gain. Menstrual disturbances and infertility are common.

Hypothyroidism can be prevented by taking adequate Iodine in diet and avoiding consanguineous marriages (in case of congenital hypothyroidism).

Hypothyroidism is a very common endocrine disorder in which the thyroid gland does not function properly. This results in a decreased production of the thyroid hormone which causes systemic defects and characteristic symptoms.

Hypothyroidism can be primary or secondary. Primary hypothyroidism is due to a defect in the thyroid gland itself causing decreased synthesis and secretion of thyroid hormones T3 and T4. This primary defect can be caused either by a deficiency in one or more of the building products of the hormones, most common of which is iodine, or it could arise from an infection in the gland's parenchyma.

Another factor which also happens to be one of the most common one is autoimmune where autoantibodies attack the thyroid gland and greatly disturb its functioning [2]. Whatever the underlying cause may be, the defect is clearly centred on the gland itself.

In the case of secondary or central hypothyroidism, the defect lies in an organ other than the thyroid gland. In this instance, the pituitary gland could be responsible as it could be releasing decreased levels of TSH or the hypothalamus may be at fault, for secreting low levels of TRH (the latter is sometimes categorised as tertiary hypothyroidism).

Whatever the cause may be, the resultant decrease of T3 and T4 hormones causes widespread effects.

Definition

Hypothyroidism is a disorder in which there is decreased or inadequate functioning of the thyroid gland leading to widespread effects.

Symptoms

The most common ones include decreased appetite, weight gain, and lethargy, swelling in the neck called goitre, decreased blood pressure, constipation, muscle pain and ankle swelling and menstrual abnormalities in females.

Prevention

The most common worldwide form of hypothyroidism can be prevented by taking adequate Iodine in diet [8].

Complications

If untreated, the disease may progress to infertility, heart defects, impaired memory and depression.

Treatment

Hormone replacement therapy successfully treats this disease.

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