Swelling at the front side of the base of the neck, ranging from a small lump to a general enlargement.
If you have hyperthyroidism (an overactive thyroid gland), you may also experience weight loss despite an increased appetite, an increased heart rate, elevated blood pressure, nervousness, diarrhea, muscle weakness, and hand tremors.
If you have hypothyroidism (an underactive thyroid gland), you may also experience lethargy, slowed physical and mental functions, depression, a lower heart rate, an intolerance to cold, constipation, easy weight gain, and tingling or numbness in your hands.
You should call the doctor if you have a large goiter and experience dizziness, hoarseness, or difficulty swallowing. The goiter may be pressing on your jugular vein, windpipe, esophagus, or the nerve that runs to your larynx. The growth requires treatment and may need to be surgically removed.