Excessive production of thyroxine causes Exophthalmic goitre.

Exophthalmic goitre, also known as Graves' disease, is a condition in which the thyroid gland produces an excessive amount of thyroxine hormone. This condition is caused by an autoimmune disorder in which the body's immune system attacks the thyroid gland, causing it to produce too much thyroxine.

Symptoms:
Excessive production of thyroxine causes the following symptoms:

1. Enlarged thyroid gland
2. Bulging eyes
3. Weight loss
4. Rapid heartbeat
5. Anxiety and irritability
6. Tremors in the hands and fingers
7. Heat intolerance
8. Sweating
9. Fatigue
10. Muscle weakness

Explanation:
The thyroid gland produces hormones that regulate metabolism, heart rate, and body temperature. Excessive production of thyroxine can disrupt these processes, leading to symptoms such as rapid heartbeat, weight loss, and heat intolerance.

In addition, the immune system's attack on the thyroid gland can cause it to become enlarged, resulting in a condition known as goitre. The bulging eyes associated with Graves' disease are caused by inflammation of the tissues behind the eyes, which can push the eyes forward.

Treatment:
Treatment for Graves' disease may include medications to regulate thyroid hormone levels and reduce inflammation, radioactive iodine therapy to destroy a portion of the thyroid gland, or surgery to remove the thyroid gland. In some cases, the symptoms of Graves' disease may resolve on their own without treatment.

(B) Exophthalmic goitre