Subacute Thyroiditis is an inflammation of the thyroid gland, often triggered by a viral infection. It typically causes pain in the neck and can lead to symptoms such as fatigue, fever, and changes in thyroid hormone levels. The condition usually affects younger adults and is more common in women. The inflammation can result in a temporary overproduction of thyroid hormones, leading to symptoms of hyperthyroidism, such as weight loss and increased heart rate. Most cases resolve on their own within a few months, but treatment may include pain relief and, in some cases, corticosteroids to reduce inflammation.