Acromegaly is a chronic condition caused by a growth hormone (GH)-secreting pituitary adenoma leading to excess production and release of GH and increased secretion of insulin-like growth factor-1 (IGF-1) from the liver [1]. Uncontrolled acromegaly with elevated hormonal levels is associated with high morbidity and mortality rates [2]. Eearlier diagnosis and improvement in disease control can lower the mortality rates in patients with acromegaly [3], approaching those of the general population.

The recommended first-line treatment for acromegaly is transsphenoidal adenoma resection if this is feasible [4], [5]. Long-term hormonal remission is achieved in no more than 50% of acromegaly patients following pituitary surgery even if performed by an experienced neurosurgeon. Medical treatment with monthly injected long-acting somatostatin receptor ligand (SRLs; octreotide, lanreotide) with high affinity for somatostatin receptor 2 (SSTR2) is given to patients who do not achieved remission after surgery [4], [5], [6]. This results in hormonal control in approximately 50% of patients, the other patients respond partially or do not respond at all. Lower baseline GH and IGF-I level and older age are good predictors of response. Other therapeutic options include the GH receptor antagonist pegvisomant administered as daily injection, and given as monotherapy, or combined with SRL. Another medical choice is the monthly injection of pasireotide LAR, a second generation SRL with high affinity for SSTR5.

Dopamine agonists (DA) are known to stimulate GH secretion in normal subjects [7], but paradoxically in patients with acromegaly DAs were shown to suppress GH hypersecretion [8]. Dopamine binding sites were demonstrated in human GH-secreting adenomas [9] and expression of dopamine receptor (DR2) was confirmed in most somatotroph adenomas studies using immunohistochemistry [*10], [11]. During the last 4 decades DAs have been extensively used in the treatment of acromegaly. Bromocriptine, a DA used since the 70’s to treat prolactin-secreting adenomas, modestly diminished the symptoms of acromegaly and suppressed GH levels, but normalized IGF-I in only 10% of patients with GH-secreting adenomas [12]. Cabergoline is an ergot derivative long-acting DR2 selective agonist administered orally and widely used in the last two decades to treat patients with prolactinomas and Parkinson’s disease. Prolactinomas have a high remission rate, 80-90%, with cabergoline. In acromegaly the role of cabergoline is limited by its relatively modest effect on achieving hormonal remission, largely restricted to patients who remain with mild GH/IGF-I increase postoperatively. Noteworthy, cabergoline is used off-label in acromegaly as it has never been approved by the FDA or other regulatory authorities for the indication of acromegaly.