Galactorrhea
Milky nipple discharge unrelated to breastfeeding
Quick Facts
- Type: Hormonal / breast condition
- Key feature: Milky discharge not linked to nursing
- Common driver: High levels of the hormone prolactin
- Can affect: Women, men, and occasionally newborns
Overview
Galactorrhea is a milky discharge from one or both nipples that is not related to the normal milk production of breastfeeding. It can affect women who are not pregnant or nursing, and less commonly it affects men. The discharge may happen spontaneously or only when the nipple is squeezed, and it can come from one or both breasts.
Galactorrhea is itself a symptom rather than a disease, and it is usually caused by something that raises the level of prolactin, the hormone that stimulates milk production. While it is often benign, it should be evaluated to find the underlying cause, which can range from medications to hormone imbalances or, less often, a small pituitary growth.
Symptoms
The main feature is abnormal nipple discharge, sometimes with related signs:
- Milky white or sometimes clear discharge from one or both nipples
- Discharge that is spontaneous or only appears with pressure
- Irregular or absent menstrual periods in women
- Decreased sex drive or, in men, erectile difficulties
- Headaches or vision changes if a pituitary growth is the cause
Discharge that is bloody, comes from only one duct, or is associated with a breast lump is different and should be promptly evaluated, as it can have other causes.
Causes
Galactorrhea usually reflects increased prolactin or breast stimulation. Common causes include:
- Medications: Certain antidepressants, antipsychotics, blood pressure medicines, and others can raise prolactin.
- Pituitary tumors: A usually benign growth called a prolactinoma can produce excess prolactin.
- Hormone imbalances: An underactive thyroid (hypothyroidism) can increase prolactin.
- Nipple stimulation: Frequent breast or nipple stimulation, or chest wall irritation.
- Other causes: Chronic kidney disease, certain herbal supplements, or, in some cases, no identifiable cause.
Risk Factors
- Taking medications known to raise prolactin
- Thyroid disease, particularly an underactive thyroid
- A history of pituitary problems
- Frequent nipple or chest stimulation
- Chronic kidney disease
Diagnosis
Evaluation aims to find the cause of the discharge:
- History and exam: Reviewing medications, menstrual history, and examining the breasts.
- Blood tests: Measuring prolactin, thyroid function, and a pregnancy test when appropriate.
- Imaging: An MRI of the pituitary if prolactin is high, and breast imaging if discharge is bloody, one-sided, or there is a lump.
Treatment
Treatment depends entirely on the underlying cause.
- Adjusting medications: If a drug is responsible, a doctor may change or stop it where safe to do so.
- Treating hormone problems: Thyroid hormone replacement for an underactive thyroid.
- Medications for high prolactin: Drugs that lower prolactin can shrink a prolactinoma and stop the discharge.
- Surgery or other treatment: Rarely needed, for larger pituitary tumors that do not respond to medication.
- Reducing stimulation: Avoiding frequent nipple stimulation when that is a factor.
When no cause is found and the discharge is harmless, reassurance and monitoring may be all that is needed.
When to See a Doctor
See a doctor if you have persistent or spontaneous milky nipple discharge that is not related to breastfeeding, especially if you also have missed periods, headaches, or vision changes. Seek prompt evaluation if nipple discharge is bloody, comes from only one breast or one duct, or is accompanied by a breast lump, as these features may point to a different condition that needs a separate workup.
Frequently Asked Questions
Is galactorrhea a sign of breast cancer?
Galactorrhea, which is milky discharge from both breasts, is usually due to hormones rather than cancer. However, discharge that is bloody, comes from one duct, or is linked to a breast lump should be evaluated promptly, as these features can have other causes.
What causes milky discharge when I'm not breastfeeding?
It is usually caused by higher levels of the hormone prolactin. Common reasons include certain medications, an underactive thyroid, a benign pituitary growth called a prolactinoma, or frequent nipple stimulation. Sometimes no cause is found.
Can men get galactorrhea?
Yes, though it is less common. In men, galactorrhea may be accompanied by reduced sex drive or breast enlargement and should be evaluated, as it can signal a hormone imbalance or pituitary problem.
How is galactorrhea diagnosed?
A doctor reviews your medications and history, examines the breasts, and orders blood tests for prolactin and thyroid function, plus a pregnancy test if appropriate. If prolactin is high, an MRI of the pituitary may be done.
How is galactorrhea treated?
Treatment targets the cause, such as changing a responsible medication, treating an underactive thyroid, or using medicine to lower prolactin and shrink a prolactinoma. If the discharge is harmless and no cause is found, monitoring may be all that is needed.
References
- Mayo Clinic. Galactorrhea — Symptoms and causes.
- MedlinePlus, U.S. National Library of Medicine. Breast discharge.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Prolactinoma.
- Office on Women's Health, U.S. Department of Health and Human Services. Nipple discharge.