Galactorrhea often results from having too much prolactin — the hormone responsible for milk production when you have a baby. Prolactin is produced by your pituitary gland, a small bean-shaped gland at the base of your brain that secretes and regulates several hormones.
Possible causes of galactorrhea include:
- Medications, such as certain sedatives, antidepressants, antipsychotics and high blood pressure drugs
- Opioid use
- Herbal supplements, such as fennel, anise or fenugreek seed
- Birth control pills
- A noncancerous pituitary tumor (prolactinoma) or other disorder of the pituitary gland
- Underactive thyroid (hypothyroidism)
- Chronic kidney disease
- Excessive breast stimulation, which may be associated with sexual activity, frequent breast self-exams with nipple manipulation or prolonged clothing friction
- Nerve damage to the chest wall from chest surgery, burns or other chest injuries
- Spinal cord surgery, injury or tumors
- Stress