Last reviewed: 7 Apr 2021
Last updated: 01 Feb 2019



History and exam

Key diagnostic factors

  • palpable thyroid nodule
  • younger age

Other diagnostic factors

  • hyperphagia
  • weight loss
  • sweating/heat intolerance
  • nervousness
  • palpitations
  • oligomenorrhea
  • hyperdefecation
  • dyspnea
  • stare or lid lag
  • tachycardia
  • tremor
  • warm moist skin
  • muscle weakness
  • hoarseness
  • dysphagia
  • choking
  • mood change

Risk factors

  • young adult age
  • iodine deficiency
  • head and neck irradiation
  • family history of thyroid nodules
  • female sex

Diagnostic investigations

1st investigations to order

  • thyroid stimulating hormone (TSH)
  • thyroid ultrasound

Investigations to consider

  • free thyroxine (T4; or total T4 with a measure of binding)
  • total T3 with a measure of binding (or free T3)
  • thyroid scan and uptake
  • metabolic panel
  • CBC
  • TSH receptor antibodies
  • thyroid peroxidase antibodies
  • ECG
  • CT neck (noncontrast)

Treatment algorithm


Associate Professor of Medicine

Boston University Medical Center




ENP has received honoraria and travel funding for speaking at two international conferences for Merck Serono and at one for IBSA. She is a member of the Management Council of the Iodine Global Network. She is an author of a number of references cited in this topic.

Dr Elizabeth N. Pearce would like to gratefully acknowledge Dr Sheila Feit, the previous contributor to this topic.

Peer reviewersVIEW ALL

Professor of Medicine

Mayo Clinic




JCM declares that he has no competing interests.

Consultant Endocrinologist

Freeman Hospital




PP declares that he has no competing interests.

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