Gigantism also called Giantism is a very rare condition that occurs during childhood, in which there is extreme bone, muscle and organ growth. Gigantism is caused by an overproduction of growth hormone (GH) that occurs before a child’s bone growth plates have closed. This results in excessive growth and abnormally tall height between 7 to 9 feet.


Gigantism is caused by an overproduction of growth hormone (GH) that occurs in childhood before the bone growth plates have closed. Diseases, disorders and conditions that can cause GH overproduction leading to gigantism include:

  • Benign tumors of the pituitary gland, which press on the pituitary gland and cause excessive GH production. This is the most common cause of gigantism.

  • Carney complex (rare gene mutation that causes a high risk of certain tumors including pituitary adenoma)

  • McCune-Albright syndrome (syndrome caused by a gene mutation)

  • Multiple endocrine neoplasia type 1 (inherited disorder that causes tumors to form in endocrine glands and makes them hyperactive)

  • Neurofibromatosis (genetic disorder causing tumor growth)


The child will grow in height, as well as in the muscles and organs.Children with Gigantism are very tall for their age and may also have the following conditions:
  • Enlarged hands, fingers, toes, head or tongue.
  • Unusually large jaw, prominent forehead, and thick facial features.
  • Delayed Puberty.
  • Excessive sweat production.

  • Headaches.

  • Irregular menstrual periods in teens.

  • Production of breast milk.

  • Double vision, problems with peripheral vision.

  • Weakness and tingling in the arms and legs due to enlarging tissues compressing nerves.


Gigantism is mainly treated through controlling the GH( growth hormone) release or blocking the effect of growth hormone. In pituitary tumors, surgery is the treatment which can cure many cases. Medical treatment includes:

  • Somatostatin analogs, such as octreotide and long-acting lanreotide which reduce GH release.
  • Dopamine agonists (bromocriptine mesylate, cabergoline) have also been used to reduce growth hormone release, but these are generally less effective.
  • GH antagonist, pegvisomant (Somavert), which blocks the effects of GH.
  • Radiation therapy is used to bring growth hormones to level but takes 5-10 years for full effect. This therapy is only used when surgery and medication fail