A patient has a high serum prolactin level with milky discharge and an MRI shows a pituitary lesion. What hormonal class should be targeted for treatment?

In this scenario, the patient is presenting with symptoms associated with hyperprolactinemia—namely, a high serum prolactin level and milky discharge—alongside imaging results that show a pituitary lesion. Prolactin is a hormone produced by lactotroph cells in the anterior pituitary, and its secretion is primarily inhibited by dopamine, which is released from the hypothalamus.

The presence of a pituitary lesion likely indicates a prolactinoma, which is a benign tumor that secretes prolactin. The primary goal of treatment in such cases is to restore normal prolactin levels and alleviate the associated symptoms. Dopamine agonists, such as cabergoline or bromocriptine, are effective in lowering prolactin levels and reducing the size of prolactin-secreting tumors.

By targeting dopamine, the treatment mimics the natural inhibitory effect of dopamine on prolactin secretion. Therefore, focusing on dopamine is the most appropriate hormonal class in this context, as it directly addresses the underlying cause of the elevated prolactin and the resulting symptoms. Using dopamine agonists is the first-line treatment for hyperprolactinemia associated with prolactinomas.