Causes of Elevated Prolactin

Prolactin is a polypeptide hormone, also known as PRL (prolactin), and is one of the hormones secreted by the pituitary gland. The primary causes of elevated prolactin levels include the following:

1. Neural stimulation. Stimulation of certain areas—particularly the chest skin—including severe pain caused by peripheral nerve injury, can transmit neural signals to the hypothalamus, thereby increasing prolactin secretion. Examples include thoracic surgery, burns, and herpes zoster affecting the chest and back.

2. Drug effects. Oral contraceptives may increase pituitary prolactin secretion while decreasing gonadotropin secretion. Prolonged use of drugs such as reserpine, chlorpromazine, and morphine alters dopamine synthesis, absorption, and metabolism, thereby inhibiting the release of prolactin-inhibiting factor (PIF) and resulting in excessive prolactin secretion.

3. Pituitary tumors. These primarily refer to various tumors arising in the pituitary gland in women, leading to hyperprolactinemia. Typical symptoms include breast tenderness, galactorrhea, oligomenorrhea, and amenorrhea.

4. Hypothalamic disorders. Diseases affecting the hypothalamus or adjacent regions in women may reduce the production of prolactin-inhibiting factor (PIF), or increase the release of thyrotropin-releasing hormone (TRH) and prolactin-releasing factor (PRF).