The thyroid is a small gland in the neck that releases hormones influencing energy, weight, mood and many other functions. When its hormone levels change, symptoms tend to appear gradually.

What the thyroid does

Thyroid hormones help regulate how the body uses energy. Too little or too much hormone can affect how a person feels, though the changes are often slow and easy to attribute to other causes.

  • Persistent tiredness or low energy
  • Unexplained weight gain or weight loss
  • Feeling unusually cold or warm
  • Changes in heart rate
  • Changes in mood or sleep
  • Swelling or a feeling of fullness in the neck

Why symptoms can be misleading

Tiredness, weight change and mood changes are common in everyday life and can have many causes — stress, sleep, diet, other conditions and medicines among them. Because of this, thyroid problems are usually confirmed through testing rather than symptoms alone.

How thyroid concerns are evaluated

  • A discussion of your symptoms and how long they have been present
  • Review of any previous thyroid reports
  • A physical examination, including the neck
  • Thyroid function testing if your doctor advises it
  • A treatment and follow-up plan based on the results
Thyroid medicines are started and adjusted only under medical supervision, based on test results. Do not begin or change thyroid medication on your own.

Why follow-up matters

Hormone levels can change over time, so periodic testing helps your doctor adjust treatment appropriately. Follow-up also provides a chance to discuss any new symptoms.

When to seek urgent care

A very fast or irregular heartbeat with weakness or breathlessness, severe drowsiness or confusion, or rapidly increasing neck swelling with difficulty breathing or swallowing needs prompt medical attention.

A final thought

If you have symptoms that could be thyroid-related, a consultation is the appropriate first step. Your doctor can decide whether testing is needed and explain what the results mean.