Galactorrhea is a milky nipple discharge unrelated to the normal milk production of breast-feeding. Galactorrhea itself isn’t a disease, but it’s a sign of an underlying problem. Although it occurs most often in women, galactorrhea can happen in men and even sometimes in infants.

Excessive breast stimulation, medication side effects, or disorders of the hypothalamus or pituitary glands all may contribute to galactorrhea. Often, galactorrhea results from increased levels of prolactin, the hormone that stimulates milk production.

Signs and symptoms associated with galactorrhea include:

  • White, yellow or green nipple discharge with no trace of blood
  • Spontaneously leaked or manually expressed nipple discharge
  • Persistent or intermittent nipple discharge
  • One or both breasts affected
  • Absent or irregular menstrual periods
  • Headaches or vision problems

When to see a doctor
If you have a persistent milky nipple discharge from one or both of your breasts and you’re not pregnant or breast-feeding, make an appointment to see your doctor. If breast stimulation triggers nipple discharge from multiple ducts, there is little cause for worry. The discharge probably doesn’t signal breast cancer, but you should still see a doctor for evaluation. Bloody or clear, spontaneous and persistent nipple discharge from one duct requires urgent medical evaluation, as it may be a sign of an underlying breast cancer.

Galactorrhea often results from too much prolactin — the hormone responsible for milk production (lactation) when you have a baby. Prolactin is produced by your pituitary gland, a marble-sized gland at the base of your brain that secretes and regulates several hormones.

Possible causes of galactorrhea include:

  • Medications, such as certain tranquilizers, antidepressants and high blood pressure drugs
  • Herbal supplements, such as fennel, anise or fenugreek seed
  • Birth control pills
  • A noncancerous pituitary tumor (prolactinoma) or other disorder of the pituitary gland
  • An underactive thyroid (hypothyroidism)
  • Chronic kidney disease
  • Excessive breast stimulation, which may be associated with sexual activity, frequent breast self-exams or prolonged clothing friction
  • Nerve damage to the chest wall from chest surgery, burns or other chest injuries
  • Spinal cord injury

Idiopathic galactorrhea
Sometimes doctors can’t find a cause for galactorrhea. This is called idiopathic galactorrhea, and it may just mean that your breast tissue is particularly sensitive to the milk-producing hormone prolactin in your blood. If you have increased sensitivity to prolactin, even normal prolactin levels can lead to galactorrhea.

Galactorrhea in men
In males, galactorrhea may be associated with testosterone deficiency (male hypogonadism). Erectile dysfunction and a lack of sexual desire also are associated with testosterone deficiency.

Galactorrhea in newborns
Galactorrhea sometimes occurs in newborns. High maternal estrogen levels cross the placenta into the baby’s blood. This can cause enlargement of the baby’s breast tissue, which may be associated with a milky nipple discharge.

pituitary gland

However, in some cases when you call to set up an appointment, you may be referred immediately to a breast health specialist.

What you can do
The initial evaluation focuses on your medical history. You’ll give details about your symptoms and any other relevant health concerns. To prepare for this discussion:

  • Take note of all your symptoms, even if they seem unrelated to the reason for which you scheduled the appointment.
  • Review key personal information, including major stresses or recent life changes.
  • Make a list of all medications, vitamins and supplements that you regularly take.
  • Write down questions to ask your doctor. List your questions from most important to least important in case time runs out.

What to expect from your doctor
Your doctor may ask you questions about:

  • The color and nature of the nipple discharge
  • Whether nipple discharge occurs in one or both breasts
  • If you have any other breast signs and symptoms, such as a breast lump or area of thickening
  • If you experience breast pain
  • How often you perform breast self-exams
  • Whether you’re pregnant or breast-feeding
  • Whether you’re still having regular menstrual periods
  • If you’re having trouble getting pregnant
  • What medications you’re taking
  • Whether you’re experiencing headaches or vision problems

What you can do in the meantime
Until your appointment, follow these tips to deal with unwanted nipple discharge:

  • Avoid breast stimulation to reduce your chances of nipple discharge. For instance, don’t touch your nipples during sexual activity. In addition, postpone breast self-exams and avoid clothing that causes too much friction on your nipples.
  • Use breast pads to absorb nipple discharge and prevent it from seeping through your clothing.

Finding the underlying cause of galactorrhea can be a complex task because there are so many possibilities.

Testing may involve:

  • A physical exam, during which your doctor may try to express some of the fluid from your nipple by gently squeezing or pressing the area around your nipple. Your doctor also checks for breast lumps or other suspicious areas of thickened breast tissue.
  • Analysis of fluid discharged from the nipple. Your doctor may do a simple test on the fluid to see whether any blood is present in the fluid.
  • A blood test, to check for the amount of prolactin in your system. If your prolactin level is elevated, your doctor might also check your thyroid-stimulating hormone (TSH) level.
  • A pregnancy test, to exclude — or confirm — pregnancy as a possible cause of the nipple discharge.
  • Mammography, ultrasound or both, to generate images of your breast tissue, if your doctor finds a breast lump or other suspicious breast tissue during your physical exam.
  • Magnetic resonance imaging (MRI) to check for a tumor or other abnormality of your pituitary gland, if your blood test reveals elevated prolactin levels.

If your doctor suspects medication use as the cause of galactorrhea, you might be instructed to stop taking the medicine for a short time, during which your doctor can assess this possible cause.

Sometimes doctors can’t determine an exact cause of galactorrhea, but it needs to be treated anyway. This might be the case if you experience bothersome or embarrassing nipple discharge. In such instances, you might be given a medication to block the effects of prolactin or to lower the amount of prolactin in your body. Reducing prolactin levels may eliminate galactorrhea.

Medication use : Stop taking medication, change dose or switch to another medication. Make medication changes only if your doctor says it’s OK to do so.

Underactive thyroid gland (hypothyroidism) : Take a medication, such as levothyroxine (Levothroid, Levoxyl, others), to counter insufficient hormone production by your thyroid gland (thyroid replacement therapy).

Pituitary tumor (prolactinoma) : Use a medication to shrink the tumor or have surgery to remove it.

Unknown cause : Try a medication to lower your prolactin level, such as bromocriptine (Parlodel) or cabergoline (Dostinex), and minimize or eliminate nipple discharge.

If galactorrhea persists and you can’t take any of the medications that might work to relieve your symptoms — or if medications aren’t working for you — surgery may be an option. In that case, your doctor may refer you to a surgeon to discuss the possibility of bilateral total duct excision — surgically removing the milk ducts from both of your breasts.

Often, the milky discharge associated with galactorrhea goes away on its own. Until that time, minimize the likelihood of nipple discharge by avoiding stimulating your breasts. These tips may help:

  • Don’t touch your nipples during sexual activity.
  • Avoid performing breast self-exams more frequently than once a month.
  • Wear clothing that minimizes friction between the fabric and your nipples.

You could also use breast pads to protect yourself from leaks that might otherwise be embarrassing.