Familial non-autoimmune autosomal dominant hyperthyroidism (FNAH) is a rare hyperthyroidism characterized by mild to severe hyperthyroidism, presence of goiter, absence of features of autoimmunity, frequent relapses while on treatment and a positive family history. The disease is MONDO_0012203 (familial hyperthyroidism due to mutations in TSH receptor). Also known as: familial non-immune hyperthyroidism, resistance to thyroid stimulating hormone.