Hyperprolactinemia

The presence of abnormally elevated serum prolactin concentrations, often associated with inappropriate milk production from the breast.

• Normal males: <20 ng/mL or <400 mIU/L

• Non-pregnant females: <25 ng/mL or <550 mIU/L

Causes

• Pituitary and hypothalamic causes

  • Pituitary adenoma (prolactinoma)

  • Hypothalamic lesions affecting dopamine inhibition of prolactin release

  • Pituitary stalk compression

  • Other sellar or parasellar tumors

• Physiological causes

  • Pregnancy

  • Breastfeeding

  • Nipple stimulation

  • Sexual activity

  • Sleep

  • Physical or emotional stress

• Hypothyroidism

• Polycystic ovary syndrome (PCOS)

• Kidney failure with reduced prolactin clearance

• Liver cirrhosis

• Chronic systemic illness

• Medications

  • Dopamine-antagonist medications

  • Antipsychotics

  • Antidepressants

  • Verapamil

  • Opioids

• Macroprolactinemia (biologically less active prolactin complexes)