Common symptoms of hyperthyroidism

Symptoms can develop gradually or become noticeable over a short time. Some people have several symptoms, while others mainly notice changes such as feeling unusually warm, losing weight without trying or being unable to settle at night.

Hyperthyroidism, also called an overactive thyroid, means the thyroid gland is producing more thyroid hormone than the body needs. This can speed up several body processes. You may notice tremor, muscle weakness, tiredness despite feeling restless, or a greater appetite alongside weight loss.

The heart may beat forcefully or quickly, which can feel like palpitations. The digestive system may become more active, causing loose stools or diarrhoea. Heat intolerance and excessive sweating can occur because the body is generating and releasing heat differently. Anxiety and difficulty sleeping can also accompany the hormone changes; these symptoms alone do not establish the cause.

Arrange a medical assessment if you have a combination of these symptoms, especially unexplained weight loss, persistent palpitations, tremor or ongoing bowel changes. A clinician will review your symptoms, examine your neck and pulse, and may request thyroid blood tests. Tell them about medicines, supplements and any previous thyroid problems.

While waiting, keep a record of when symptoms began and whether they follow caffeine, exertion or stressful events. Choose fluids regularly if sweating or diarrhoea is present, and avoid taking thyroid medicine or iodine-containing supplements unless a clinician has advised them.

Seek urgent medical help for chest pain, fainting, severe breathlessness, confusion, a very fast or irregular heartbeat, or marked weakness with a high temperature. These symptoms can signal a serious problem and should not be assessed through a symptom list alone.

If symptoms are troublesome but not urgent, book an appointment soon. Prompt assessment is particularly sensible when symptoms are worsening, disrupting sleep, or affecting daily activities.

You could ask: Could my symptoms be related to an overactive thyroid? Which blood tests would clarify this? Could any medicine or supplement be contributing? What symptoms should prompt urgent care? If treatment is needed, how will we monitor my heart rate and thyroid levels?