Final answer:
Irritability, tachycardia, and weight loss are signs of hyperthyroidism, specifically Graves' disease. This condition is caused by an antibody that stimulates the thyroid to produce excess hormones, causing these symptoms along with goiter and exophthalmia.
Step-by-step explanation:
Irritability, tachycardia (rapid heartbeat), and weight loss are common signs of a thyroid disease known as hyperthyroidism. One specific form of this condition is Graves' disease, which is the most prevalent cause of hyperthyroidism in the United States. Symptoms of Graves' disease occur due to the production of thyroid-stimulating immunoglobulin (TSI), an antibody that can overstimulate the thyroid leading to excessive thyroid hormone production. This can result in increased metabolism, heat intolerance, goiter (an enlarged thyroid gland), and exophthalmia (bulging eyes), also known as Graves' ophthalmopathy.
Hyperthyroidism can be managed with medications that mitigate these symptoms by reducing thyroid hormone production or by more drastic measures like surgery or radioactive iodine treatment, resulting in the removal or destruction of the thyroid gland. After such treatments, patients may require medication to replace the thyroid hormones that their bodies can no longer produce.