Summary
Definition
History and exam
Key diagnostic factors
- nonspecific symptoms
Other diagnostic factors
- lethargy
- constipation
- weight gain
- depression
- menstrual irregularity
- dry or coarse skin
- change in voice
- bradycardia
- hypertension
- delayed relaxation of tendon reflexes
- cold sensitivity
- coarse hair
- eyelid edema
- goiter
Risk factors
- iodine deficiency
- female sex
- middle age
- family history of autoimmune thyroiditis
- autoimmune disorders
- treatment for thyroid disease
- postpartum thyroiditis
- Turner and Down syndromes
- type 1 diabetes
- radiation therapy to head and neck
- infiltrative disease
- iodine excess
- amiodarone use
- lithium use
Diagnostic investigations
1st investigations to order
- serum thyroid-stimulating hormone (TSH)
Investigations to consider
- free serum thyroxine (T4)
- antithyroid peroxidase antibodies
- CBC
- fasting blood glucose
- serum cholesterol
Treatment algorithm
confirmed overt primary hypothyroidism
subclinical hypothyroidism with TSH >10 mIU/L
Contributors
Authors
Wail Malaty, MD
Adjunct Clinical Professor
Department of Family Medicine
University of North Carolina
Chapel Hill
NC
Disclosures
WM declares that he has no competing interests.
Peer reviewers
Sun Y. Lee, MD, MSc
Assistant Professor of Medicine
Boston University School of Medicine
Boston
MA
Disclosures
SYL declares that she has no competing interests.
Salman Razvi, MD, FRCP
Consultant Endocrinologist
Queen Elizabeth Hospital
Gateshead
UK
Disclosures
SR declares that he has no competing interests.
Lakdasa Premawardhana, MBBS, FRCP, FRCPE
Consultant Physician
Caerphilly Miners' Hospital
Caerphilly
UK
Disclosures
LP declares that he has no competing interests.
Birte Nygaard, MD, PhD
Associated Professor
Consultant Endocrinologist
Herlev Hospital
University of Copenhagen
Denmark
Disclosures
BN declares that she has no competing interests.
Differentials
- Central or secondary hypothyroidism
- Depression
- Alzheimer dementia
More DifferentialsGuidelines
- Thyroid disease in pregnancy
- Asymptomatic thyroid dysfunction (2019)
More GuidelinesPatient leaflets
Underactive thyroid
Underactive thyroid: questions to ask your doctor
More Patient leafletsLog in or subscribe to access all of BMJ Best Practice
Use of this content is subject to our disclaimer