Myxedema Coma or Crisis Clinical Presentation

Updated: Aug 31, 2020
  • Author: Mohsen S Eledrisi, MD, FACP, FACE; Chief Editor: George T Griffing, MD  more...
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Most patients with myxedema coma have a history of hypothyroidism. Some patients may have developed hypothyroidism after thyroidectomy or iodine therapy for hyperthyroidism. However, some patients will have undiagnosed hypothyroidism and myxedema coma will be the initial presentation.

Symptoms of hypothyroidism, including fatigue, weight gain, cold intolerance, constipation, and dry skin, may be elicited.

Patients have depressed mental state with lethargy, delirium, or coma.

Symptoms of the precipitating illness can be seen, such as infection (commonly pneumonia), stroke, myocardial infarction, trauma, or heart failure.



Myxedema coma is a physiologic decompensation of untreated hypothyroidism that is usually caused by a precipitating factor such as the following:  

  • Infection
  • Exposure to cold temperatures
  • Trauma
  • Burns
  • Cerebrovascular accident
  • Myocardial infarction
  • Congestive heart failure
  • Respiratory acidosis
  • Medications such as the following:
    • Tranquilizers
    • Sedatives
    • Anesthetics
    • Narcotics
    • Amiodarone
    • Rifampin
    • Beta blockers
    • Lithium
    • Phenytoin
  • Gastrointestinal hemorrhage
  • Metabolic disturbances such as hypoglycemia, hyponatremia, acidosis, and hypercapnia
  • Ingestion of raw bok choy

Physical Examination

Physical findings may include the following:

  • Hypothermia, which may not be recognized initially because many automatic thermometers do not register low body temperatures (It may be necessary to use special thermometers.)
  • Hypotension
  • Bradycardia
  • Decreased pulse pressure, normal systolic pressure, elevated diastolic pressure
  • Decreased respiratory rate
  • Periorbital puffiness
  • Macroglossia
  • Coarse or thinning hair
  • Thyroid is commonly small (Look for scar suggesting previous thyroidectomy.)
  • Slow respiratory rate
  • Signs of pleural effusion
  • Soft or distant heart sounds, diminished apical impulse, pericardial effusion
  • Abdominal distention due to ascites
  • Diminished or absent bowel sounds due to ileus
  • Bladder distention
  • Cold extremities, nonpitting edema of the upper and lower extremities
  • Cool, pale, dry, scaly, and thickened skin
  • Dry, brittle nails
  • Ecchymoses, purpura
  • Confusion, stupor, slow speech, delayed reflexes, seizures, coma


Complications may include the following:

  • Respiratory failure
  • Coma
  • Heart failure
  • Myocardial infarction
  • Sepsis
  • Gastrointestinal bleeding