Nipple Discharge: what it usually means
Also searched as: discharge from nipple, leaking nipple, breast discharge · Updated 19 Aug 2026 · Educational — not medical advice
The short answer: Nipple discharge outside of pregnancy or breastfeeding can be normal — a few drops of clear or milky fluid when the nipple is squeezed is common — but bloody discharge, discharge from a single duct, or fluid that leaks on its own without squeezing needs prompt evaluation. Milky discharge unrelated to breastfeeding can signal a prolactin hormone imbalance, sometimes from a small pituitary growth or certain medications, and is worth a blood test.
See a doctor promptly if…
Bloody or rust-colored discharge from the nipple needs prompt evaluation.
Discharge that comes from a single duct and happens spontaneously, without squeezing, needs prompt evaluation.
Discharge paired with a new lump, skin changes, or nipple retraction needs prompt evaluation.
Milky discharge unrelated to pregnancy or breastfeeding, especially with irregular periods or headaches, needs evaluation for a prolactin imbalance.
Common causes
- Elevated prolactin — A pituitary adenoma, thyroid problems, or certain medications can raise prolactin and cause milky discharge unrelated to breastfeeding.
- Fibrocystic breast changes — Benign lumpy breast tissue can occasionally produce clear or greenish discharge from multiple ducts.
- Duct ectasia — Age-related widening of a milk duct near the nipple causes thick, sticky discharge, often near menopause.
- Intraductal papilloma — A small, usually benign growth inside a duct that commonly causes bloody or sticky discharge from a single duct.
- Infection — Mastitis or a duct infection can cause pus-like discharge along with redness and pain.
- Medications — Some antipsychotics, blood pressure drugs, and hormonal treatments raise prolactin and trigger discharge as a side effect.
What helps
- Avoid repeatedly squeezing or checking the nipple, since this can trigger or worsen discharge.
- Wear a supportive bra to reduce friction and irritation.
- Note the color, whether it's from one or both breasts, and whether it happens on its own or only with squeezing, to describe clearly to a doctor.
Which doctor to consult
A breast specialist or gynecologist can examine the discharge, order a prolactin and thyroid check, and arrange imaging if needed. Bloody or single-duct discharge should be evaluated promptly rather than watched.
Lab tests doctors often check
If this symptom persists, these are the values a doctor commonly looks at — and if you already have a report, the analyzer explains where you stand.
Questions people ask
Is milky nipple discharge always related to breastfeeding?
No. Milky discharge unrelated to pregnancy or breastfeeding, called galactorrhea, is usually caused by elevated prolactin — a hormone that can rise due to a small pituitary growth, thyroid imbalance, or certain medications. A blood test for prolactin and thyroid function usually identifies the cause.
Is bloody nipple discharge always a sign of cancer?
Not always — the most common cause of bloody discharge is a small, benign growth inside a duct called an intraductal papilloma. However, because bloody or single-duct discharge can occasionally signal something more serious, it should always be evaluated promptly with an exam and imaging rather than watched.
Related symptoms
This guide is educational and doesn't replace a clinical assessment. If a symptom is severe, rapidly worsening, or worrying you, see a doctor — being checked and reassured is never a wasted visit.