Hypothyroidism is the abbreviation for hypothyroidism. There is no standardized criteria for how long a patient with Hashimoto’s thyroiditis develops hypothyroidism; some patients may develop hypothyroidism within a few months, while others may not develop hypothyroidism for decades or even for life. Hashimoto’s thyroiditis is an autoimmune inflammation of the thyroid gland, and most patients have changes in thyroid function, with mild hyperthyroidism (hyperthyroidism) early in the course of the disease and hypothyroidism later in the course of the disease. Hypothyroidism is the first symptom in about 60% of patients. Hashimoto’s thyroiditis progresses slowly and can remain unchanged for many years, with a few cases resolving on their own, while most patients will eventually develop hypothyroidism. Patients diagnosed with Hashimoto’s thyroiditis can have regular checkups to monitor their thyroid function to help detect hypothyroidism.