When to worry about night sweats with hyperthyroidism

Night sweats are a common presentation of hyperthyroidism, but recurrent or drenching sweats should be discussed with a clinician, especially with other changing symptoms. The thyroid can increase the body's heat production and make sweating easier, including during sleep. Night sweating can also have other causes, so it should be considered alongside your thyroid symptoms, examination and test results.

Most people with hyperthyroidism notice symptoms such as heat intolerance, a racing or pounding heartbeat, shakiness, restlessness, trouble sleeping, more frequent bowel movements or unplanned weight loss. Night sweats may become more noticeable when thyroid hormone levels are still high, treatment has been missed or a dose needs reassessment. They can also occur with a warm bedroom, alcohol, medicines, infection or hormonal changes. A new pattern does not identify one cause by itself.

Keep a brief record of when the sweating happens, whether you need to change clothes or bedding, your temperature if you feel feverish, and any palpitations, tremor or weight change. Take prescribed thyroid medicine exactly as directed and do not change the dose or stop it without medical advice. Arrange a routine appointment if the sweats persist, interrupt sleep, return after improving, or occur with worsening thyroid symptoms. A clinician may review your medicines and repeat thyroid blood tests.

Seek emergency help for severe sweating with a very fast or irregular heartbeat, chest pain, difficulty breathing, fainting, severe weakness, high fever, vomiting, diarrhoea, agitation or confusion. These symptoms can signal a serious complication of uncontrolled hyperthyroidism, including thyroid storm. Do not drive yourself if you feel faint, confused or severely unwell. For less urgent concerns, contact your treating clinician promptly if symptoms are steadily worsening or you cannot keep fluids down.

Ask whether your current symptoms suggest that your thyroid levels need checking, whether any medicine or supplement could be contributing to sweating, and what signs should prompt same-day advice. Tell the clinician about recent medication changes, missed doses, fever, infections, alcohol use and sleep disruption. If you monitor your pulse, bring the pattern rather than relying on a single reading.