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Hypothyroidism and Myxedema Coma Clinical Presentation

  • Author: Erik D Schraga, MD; Chief Editor: Romesh Khardori, MD, PhD, FACP  more...
Updated: Dec 11, 2015


The symptoms characteristic of hypothyroidism are numerous yet often vague and subtle, especially in early stages of the disease. Note the following:

  • Lethargy
  • Generalized weakness
  • Brittle or thinning hair
  • Menstrual irregularity
  • Menorrhagia
  • Forgetfulness
  • Fullness in throat
  • Deep, husky voice secondary to mucopolysaccharide infiltration of the vocal cords
  • Cold intolerance
  • Weight gain
  • Muscle/joint pain or weakness
  • Inability to concentrate
  • Headaches
  • Constipation
  • Emotional lability
  • Depression
  • Blurred vision
  • Dry hair


Potential physical examination findings include the following:

  • Pseudomyotonic reflexes - Prolonged relaxation phase, usually at least twice as long as the contraction phase
  • Hypothermia (especially in myxedema coma)
  • Skin changes - Dry, cool, coarse, and thickened with a yellowish appearance
  • Subcutaneous tissues - Nonpitting, waxy, dry edema, secondary to accumulation of polysaccharides
  • Loss of axillary and pubic hair
  • Pallor
  • Loss of outer one third of eyebrows
  • Abdominal distention
  • Goiter
  • Unsteady gait/ataxia
  • Pericardial effusion
  • Dull facial expression
  • Coarsening or huskiness of voice
  • Periorbital edema
  • Bradycardia, narrow pulse pressure
  • Macroglossia
  • Thyroidectomy scar - In patients with altered mental status, suggests myxedema coma as a potential cause


The most common etiology of hypothyroidism worldwide is iodine deficiency as associated with endemic goiter. Conversely, a study among Chinese patients also demonstrated a significant increase in overt hypothyroidism in those with an excessive intake of iodine.[4] Within the United States and developed nations, the major causes of hypothyroidism are autoimmune destruction of the thyroid gland (eg, Hashimoto thyroiditis) and iatrogenic secondary to the treatment of Graves disease (surgical or radioactive iodine ablation of the thyroid gland). Primary hypothyroidism (dysfunction of the thyroid gland) accounts for up to 90-95% of cases. Secondary hypothyroidism (dysfunction of the pituitary or hypothalamus) accounts for most of the remainder of cases. ED management rarely requires distinguishing between primary and secondary origins.

Primary causes include autoimmune, idiopathic, postoperative, and congenital etiologies; radiation; radioiodine therapy; iodine deficiency; metabolic disorders; and medications (eg, lithium, amiodarone, phenytoin, carbamazepine, iodides). Furthermore, those with underlying autoimmune thyroiditis are susceptible to disease progression while taking these medications. Antineoplastic agents are also recognized to cause thyroid dysfunction in 20-50% of patients. Since symptoms of hypothyroidism may be vague and attributed to adverse effects of medication, it may be appropriate to monitor thyroid function regularly during treatment.[5]

Secondary causes include pituitary and hypothalamic disorders such as trauma, neoplasm, irradiation, and infiltrative diseases including sarcoidosis or amyloidosis.

In a patient with underlying hypothyroidism, inciting factors responsible for developing myxedema coma are numerous and include infection, trauma, cold exposure, or medications such as sedatives and anesthetics.

Contributor Information and Disclosures

Erik D Schraga, MD Staff Physician, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Howard A Bessen, MD Professor of Medicine, Department of Emergency Medicine, University of California, Los Angeles, David Geffen School of Medicine; Program Director, Harbor-UCLA Medical Center

Howard A Bessen, MD is a member of the following medical societies: American College of Emergency Physicians

Disclosure: Nothing to disclose.

Chief Editor

Romesh Khardori, MD, PhD, FACP Professor of Endocrinology, Director of Training Program, Division of Endocrinology, Diabetes and Metabolism, Strelitz Diabetes and Endocrine Disorders Institute, Department of Internal Medicine, Eastern Virginia Medical School

Romesh Khardori, MD, PhD, FACP is a member of the following medical societies: American Association of Clinical Endocrinologists, American College of Physicians, American Diabetes Association, Endocrine Society

Disclosure: Nothing to disclose.


Jerome FX Naradzay, MD, FACEP Medical Director, Consulting Staff, Department of Emergency Medicine, Maria Parham Hospital; Medical Examiner, Vance County, North Carolina

Jerome FX Naradzay, MD, FACEP is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, and Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

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Pericardial effusion. Note the "water-bottle" appearance of the cardiac silhouette.
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