Understanding Hypothyroidism
Thyroid hormones influence energy use and many body functions. Symptoms may include fatigue, feeling cold, constipation, dry skin, and weight gain, but these symptoms can have other causes. Some people have mild or few symptoms.
How it is assessed or used in care
Blood tests, commonly TSH and free T4, help establish the diagnosis. Causes include autoimmune thyroid disease and certain treatments or medications. When treatment is needed, thyroid hormone replacement is commonly used and monitored with follow-up testing.
What to discuss with your clinician
Ask how and when to take prescribed medication and whether other medicines or supplements affect absorption. Tell your clinician if symptoms change or if you become pregnant. Do not adjust the dose based only on symptoms or add thyroid supplements independently.
Medical references
Sources accessed November 13, 2026.
This information is for general education, not a diagnosis or an individualized treatment plan. Discuss symptoms, test results, and treatment decisions with a qualified clinician. For a medical emergency, call 911.