Medications for Pituitary Tumors: An Overview of Their Functions, Potential Side Effects
In the realm of endocrine disorders, pituitary tumors are a common concern. These growths in the pituitary gland can disrupt hormone production, leading to a variety of symptoms. Here's a breakdown of the common medications used to treat different types of pituitary tumors.
Prolactinomas, which are tumors that produce excess prolactin hormone, are typically treated with dopamine agonists such as bromocriptine and cabergoline. These drugs effectively reduce prolactin secretion and tumor size [5].
For Growth Hormone (GH)-secreting tumors, commonly known as somatotroph adenomas causing acromegaly, medications like somatostatin analogs (SSAs) are commonly used. Examples include octreotide and lanreotide, which inhibit GH secretion. Additionally, pegvisomant, a GH receptor antagonist, blocks GH action. While these drugs can be effective, it's essential to note that they do not shrink the tumor [3][5].
Adrenocorticotropic Hormone (ACTH)-secreting tumors, such as Cushing’s disease, are treated with steroidogenesis inhibitors like ketoconazole, metyrapone, etomidate, and mitotane to reduce cortisol production. Newer targeted therapies include pasireotide, a somatostatin analog that suppresses ACTH secretion, and mifepristone, a glucocorticoid receptor antagonist that blocks cortisol effects [4].
Aggressive or recurrent non-functioning or other pituitary tumors may require temozolomide (TMZ), an alkylating chemotherapeutic agent, which damages tumor DNA and induces apoptosis. Clinical trials are also exploring immune checkpoint inhibitors like nivolumab and ipilimumab for aggressive pituitary tumors [1].
It's crucial to remember that the right treatment for pituitary tumors depends on whether the tumor is cancerous, growing in size, or secreting hormones. For aggressive pituitary cancers, a person may need chemotherapy or surgery in addition to the same drugs used for other tumors.
In some cases, antipsychotic drugs like risperidone can increase prolactin levels and are associated with pituitary microadenomas, but these are drug-induced and may be reversible with medication changes [2]. Radiation therapy is generally reserved for recurrent tumors or cases unresponsive to medication or surgery [5].
Dopamine agonists, such as cabergoline and bromocriptine, are often prescribed for prolactinomas, as they prevent tumors from producing too much prolactin and can help shrink the tumor. However, these drugs must be prescribed in higher doses for ACTH-secreting tumors, leading to an increased likelihood of side effects [5].
For those experiencing fertility issues due to high prolactin levels, dopamine agonists may actually increase fertility [6].
It's important to consult an endocrinologist for treatment guidance, as the approach to treating pituitary tumors reflects the tumor type, hormone secretion, and behavior, aiming to control hormone excess and tumor size while minimizing side effects.
