Hashimoto’s thyroiditis combined with hyperthyroidism may be related to inflammation that damages the thyroid gland and causes excessive thyroid hormone release. Hyperthyroidism is caused by the overproduction of thyroid hormone by the thyroid gland itself. A common cause is viral diffuse goiter, which is an autoimmune disorder of the thyroid gland. Hashimoto’s thyroiditis is also an autoimmune inflammation of the thyroid gland. Some people with Hashimoto’s thyroiditis have hyperthyroidism, a condition called Hashimoto’s hyperthyroidism. It may be related to inflammation that damages the thyroid glands, resulting in the release of too much thyroid hormone and causing hyperthyroidism to manifest. When patients have Hashimoto’s thyroiditis combined with hyperthyroidism, it is recommended that they seek timely medical attention, follow the doctor’s instructions for further examination, and choose a reasonable treatment plan under the doctor’s comprehensive analysis.