- Pharmacologic therapy for acromegaly should be considered when surgery and irradiation are contraindicated, when there is poor likelihood of surgical success, when rapid control of symptoms is needed, or when other treatments have failed to normalize growth hormone (GH) and insulin-like growth factor-1 (IGF-1) concentrations.
- Pharmacotherapy for acromegaly using dopamine agonists provides advantages of oral dosing and reduced cost compared to somatostatin analogs and pegvisomant. However, dopamine agonists effectively normalize IGF-1 concentrations in only 10% of patients. Therefore, somatostatin analogs remain the mainstay of therapy.
- Blood glucose concentrations should be monitored frequently in the early stages of somatostatin analog therapy in all acromegalic patients.
- Pegvisomant appears to be the most effective agent for normalizing IGF-1 concentrations. However, further study is needed to determine the long-term safety and efficacy of this agent for the treatment of acromegaly.
- Recombinant GH is currently considered the mainstay of therapy for treatment of children with growth hormone-deficient (GHD) short stature. Prompt diagnosis of GHD and initiation of replacement therapy with recombinant GH is crucial for optimizing final adult heights.
- All GH products are generally considered to be equally efficacious. The recommended dose for treatment of GHD short stature in children is 0.3 mg/kg/wk.
- Pharmacologic agents that antagonize dopamine or increase the release of prolactin can induce hyperprolactinemia. Discontinuation of the offending medication and initiation of an appropriate therapeutic alternative usually normalize serum prolactin concentrations.
- Cabergoline appears to be more effective than bromocriptine for the medical management of prolactinomas and offers the advantage of less-frequent dosing and fewer adverse effects.
- Although preliminary data do not suggest cabergoline has significant teratogenic potential, cabergoline is not recommended for use during pregnancy, and patients receiving cabergoline who plan to become pregnant should discontinue the medication as soon as pregnancy is detected.
- Pharmacologic treatment of panhypopituitarism consists of glucocorticoids, thyroid hormone preparations, sex steroids, and recombinant GH, where appropriate, as lifelong replacement therapy.
On completion of this chapter, the reader will be able to:
Understand the physiology of the human pituitary gland and the primary functions of anterior and posterior pituitary hormones.
Explain the underlying pathophysiology of acromegaly and describe the typical clinical features of acromegalic patients.
Discuss the role of drug therapy, transsphenoidal surgery, and radiation therapy for patients diagnosed with acromegaly.
Design an appropriate pharmacologic treatment plan for an acromegalic patient based on patient-specific factors.
Formulate appropriate patient-counseling information to be provided to an acromegalic patient receiving somatostatin analog therapy.
Describe the typical clinical features of patients with growth-hormone–deficient short stature.
Explain current methods for diagnosis of growth-hormone–deficient short stature.
Propose an appropriate monitoring plan for a patient given recombinant human growth hormone.
Discuss the different etiologies of persistent elevated serum prolactin, and describe the typical clinical features of patients diagnosed with hyperprolactinemia.
List common pharmacologic agents that can potentially induce hyperprolactinemia.
Describe the role of clinical observation, drug therapy, transsphenoidal surgery, and radiation therapy in the management of prolactinoma.
Discuss clinically important differences between dopamine agonists ...