What is Hyperthyroidism?
Signs of Hyperthyroidism:
Under the influence of an increased level of thyroid hormones, the heart beat becomes faster, the pulse can be felt as racing. The patient feels irritable and restless. There may be weight loss in spite of a good diet. There may be insomnia, anxiety and nervousness. Fine tremors may be noticeable in the hands. There may be enlargement of the gland due to it's overworking.
Other signs and symptoms of an over active thyroid include feeling excessively hot in normal or cold temperatures, frequent bowel movements, increased appetite, loss of weight, excessive sweating, difficulty in concentration, joint pains, scant or absent menstrual periods, worsening of chest pain in patients with heart disease, worsening of breathlessness in patients with heart failure, muscle weakness of shoulders and thighs, thinning of the bones and atrial fibrillation that is, abnormally fast heart rate.
Watch out for additional symptoms:
Cause behind this increased production:
In most cases toxic nodules which develop in the thyroid are to blame. These nodules produce thyroid hormones independent of the stimulus from the pituitary. These rebel nodules keep on and producing the thyroid hormones in spite of no TSH from the pituitary.
This condition is called toxic multi-nodular goitre and usually occurs in people over 60 years. The gland may be visibly enlarged and seen as a goitre on the front of the neck.
Sometimes, there is only one single nodule which is causing all the havoc. This solitary toxic adenoma produces excessive thyroid hormones in the same way. However, not all nodules of the thyroid are toxic. There are certain fluid-filled cysts and adenomas which are harmless enough in that way. They do not produce hormones. Even cancerous nodules are not toxic.
Just as autoimmune disease can cause hypothyroidism, an autoimmune disease called Grave's disease can cause the reverse. It can stimulate an increased production of hormone or hyperthyroidism. In Grave's disease the antibodies thyrotropin receptor antibodies (TRAb), including one kind known as the thyroid-stimulating immunoglobulins (TSIs) act like TSH and cause the gland to overproduce. Eye symptoms and exopthalmus are a feature of this Grave's disease.