Most people with gigantism may reach a height of 2.5 or 2.6 meters. However, the condition of the patient varies and the maximum height that can be achieved is not exactly the same for each patient. Gigantism is caused by an overproduction of growth hormone in the body. Gigantism develops before the epiphysis closes; after puberty when the epiphyses have fused, acromegaly develops; and in a few patients, the disease starts in puberty and continues to develop into acromegaly in adulthood. Patients with gigantism may present with a peculiar body shape, hypertrophy of internal organs, and a series of endocrine metabolic disorders, including diabetes mellitus, hyperinsulinemia, and so on. Gigantism can be diagnosed by growth hormone assay, insulin-like growth factor assay, calcium and phosphorus assay, and X-ray examination. Patients who suspect gigantism need to consult regular hospitals, complete the relevant examinations, make a clear diagnosis and then timely treatment.