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Overactive thyroid

With an overactive thyroid, there is too much thyroid hormone in the body. Palpitations, weight loss, trembling and heat intolerance are common, but the cause must be established through blood tests; high fever, severe agitation and a very fast heart rate can indicate a rare thyroid storm.

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With an overactive thyroid, there is too much thyroid hormone in the body. Palpitations, weight loss, trembling and heat intolerance are common, but the cause must be established through blood tests; high fever, severe agitation and a very fast heart rate can indicate a rare thyroid storm.

  • Palpitations, a fast or irregular pulse and becoming breathless more easily.
  • Weight loss despite a normal or increased appetite and loss of muscle strength.
  • Take medicines at regular times and do not stop antithyroid medicines or beta-blockers suddenly without advice.
  • Report fever, sore throat, mouth ulcers, jaundice or dark urine immediately when taking an antithyroid medicine.
  • Make an appointment for persistent palpitations, trembling, unexplained weight loss, heat intolerance or an abnormal thyroid result.
  • For urgent GP care outside normal opening hours, call HAP 9252. Call Ambulance 912 only for an immediately life-threatening situation.

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Underactive thyroidWith an underactive thyroid, the body produces too little thyroid hormone. Symptoms often develop gradually and are non-specific; blood tests confirm the diagnosis. Levothyroxine helps when treatment is needed, but the dose and monitoring must be tailored to the individual.
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