You suffer from hyperthyroidism when your thyroid gland produces an extra amount of thyroxine hormone. Body's metabolism can be increased by hyperthyroidism which can cause an increased heartbeat that can be irregular and even weight loss.

Weight loss, despite of your appetite and food intake stays the same or increases, rapid and irregular heartbeat, nervousness, anxiety and irritability, tremors, sweating, changes in menstrual patterns, increased sensitivity to heat, more frequent bowel movements, fatigue, muscle weakness, difficulty sleeping, brittle hairs are the symptoms of hyperthyroidism.

There are many causes leading to hyperthyroidism. In Graves' disease, too much T4 is produced by thyroid that is stimulated by the antibodies produced by the immune system. In Plummer's disease, one or more adenomas, a benign tumour of your thyroid gland, creates too much T4. In thyroiditis, sometimes due to unknown reasons or due to an autoimmune condition the gland gets inflamed after pregnancy.

Doctor will check for tremor in your fingers, abnormal reflexes, change in eyes, moist and warm skin, enlarged or tender thyroid gland as you swallow and check your pulse to see if it is rapid or irregular. Blood test is done to measure thyroxine and thyroid-stimulating hormone (TSH). An overactive thyroid can be identified by a low or nonexistent amounts of TSH or an Increased level of thyroxine.

Depending on your physical condition, age, any underlying cause, the severity of the disorder and personal preference treatment is done. Oral therapy includes radioactive iodine, anti-thyroid medications, beta-blockers which prevent the thyroid gland from producing excess amounts of hormones. If you are pregnant or you otherwise cannot tolerate oral drugs, thyroid surgery is an option.