Oral glucose tolerance test (OGTT): this is used to confirm a diagnosis. Glucose normally suppresses GH. In acromegaly, GH will not be suppressed after an OGTT.
Blood glucose, calcium, phosphate and triglycerides: these may be raised in acromegaly.
Pituitary assessment (prolactin, cortisol, thyroid function tests, FSH/LH, oestradiol and testosterone): to assess pituitary function.
Serum growth hormone is not routinely used due to GH pulses throughout the day and at times of stress
Relevant imaging for acromegaly include:2
MRI pituitary: to investigate for a pituitary adenoma
The goal of management is to normalise hormone levels and remove the pituitary adenoma (if possible).
Surgical removal of the pituitary adenoma is usually performed via transsphenoidal surgery. This is the initial treatment for most patients and involves making an incision in the nose (sphenoid sinus) to allow access to the pituitary adenoma.6
Patients can be considered cured after surgery but will need regular follow-up.5
Medical management is normally used as adjuvant treatment or for patients where surgery is not recommended.3
Somatostatin analogues inhibit the release of growth hormone. Examples include octreotide and lanreotide.2
These medications do not cure acromegaly, but they have been shown to reduce tumour size.3
Gastrointestinal side effects are common and include symptoms such as cramping, bloating and diarrhoea. These symptoms occur initially after starting treatment but usually resolve once established on the medication. Up to 20% of patients can develop gallstones.6
Growth hormone receptor antagonists
Pegvisomant inhibits the synthesis of IGF-1 by acting as a growth hormone receptor antagonist.2 It is used as a second-line option if somatostatin analogues fail to control symptoms or hormone levels.3
Growth hormone antagonists can cause abnormalities in liver function. This is usually reversible and liver function tests should be monitored.6
Dopamine agonists (e.g. bromocriptine and cabergoline) work by binding to dopamine receptors in the pituitary which suppresses GH secretion. They also suppress prolactin secretion.3
Side effects of dopamine agonists include nausea, fatigue, dizziness due to postural hypotension and nightmares.6
Pituitary radiotherapy (most often, stereotactic gamma-knife) is used when there is a failure of surgical or medical treatment and can be used in combination with medical therapy.3
Radiotherapy carries the risk of hypopituitarism which can affect fertility.1
Long term monitoring
It’s important to follow up patients to monitor disease activity and complications that can result from acromegaly.
Disease activity monitoring includes:6
Change in signs and symptoms
Pituitary hormone tests: TFT, cortisol, prolactin, oestradiol and testosterone
MRI pituitary: to monitor the size of the adenoma.
Dineen R, Stewart P, Sherlock M. Acromegaly – Diagnosis and Clinical Management. QJM [Internet]. 2016. Available from: [LINK]
Adigun, O., Nguyen, M., Fox, T. and Anastasopoulou, C., 2022. Acromegaly. [online] Ncbi.nlm.nih.gov. Available from: [LINK]
Behari S, Banerji D, Das N, Sharma S, Jindal Y, Jain V. Surgical management of acromegaly: Long term functional outcome analysis and assessment of recurrent/residual disease. Asian Journal of Neurosurgery [Internet]. 2016 ;11(3):261. Available from: [LINK]
Melmed S, Katznelson L. UpToDate [Internet]. Uptodate.com. 2022. Available from: [LINK]
Figure 1. Mikael Haggstrom. Endocrine growth regulation. Licence: [Public domain]