Acromegaly Patient Information Fact Sheet

What tests confirm a diagnosis of acromegaly?
If your doctor thinks you may have acromegaly, you will be referred to a specialist, such as an endocrinologist. The specialist will give you a sugary drink and will then monitor the levels of sugar and growth hormone in your blood over the next two to three hours. If your growth hormone levels remain high throughout the test, then you have acromegaly. Physicians can also measure insulin-like growth factor I (IGF-I) levels, a protein which increase as growth hormone levels increase in people with suspected acromegaly. Elevated IGF-I levels almost always indicate acromegaly. However, a pregnant woman’s IGF-I levels are two to three times higher than normal. Also, IGF-I levels decline with age and may be abnormally low in people will poorly controlled diabetes or liver or kidney disease. If the test for acromegaly is positive, an MRI scan of the pituitary is done to locate and detect the size of the tumor.

How is acromegaly treated?
Surgical removal of the pituitary gland is the first line option and may be necessary if it is large and is causing increasing hormonal problems. Alternatively, radiotherapy may be used to destroy the part of the pituitary gland that is causing the problem.

In some cases, drug treatment may be prescribed to regulate the release of growth hormone. Drugs used to treat acromegaly include lanreotide (Somatuline Depot) and octreotide (Sandostatin and Sandostatin LAR Depot). These drugs are given by injection. For short-term treatment, before surgery or radiation therapy, octreotide (as Sandostatin) needs to be given three times a day. For long-term treatment, injections of lanreotide or octreotide (as Sandostatin LAR) may be given at intervals of one to four weeks. Pegvisomant (Somavert) is another injectable drug that may be used if other treatments are ineffective or are not tolerated. Recent studies suggest that pegvisomant may be useful in patients with glucose intolerance or overt type 2 diabetes. Bromocriptine (eg, Parlodel), a dopamine agonist, is another drug that is sometimes used to treat acromegaly. It suppresses the release of the hormone prolactin and can also reduce levels of growth hormone. It is given in tablet form. More recent studies suggest that cabergoline, a more selective dopamine agonist, may be effective in a larger number patients.

Further information
National Institutes of Health:
National Endocrine and Metabolic Diseases Information Service:
American Association of Clinical Endocrinologist:

Last Reviewed: May 2013