Nipple Discharge Colors, Causes and Treatment

Nipple discharge comes in many types, colors and consistencies. When you visit the doctor for breast discharge, your care team will ask questions about your specific type of discharge. Discharge may range in color from clear to green to brown. It can also vary in consistency and be watery, thick or sticky. Sometimes, discharge only happens when you press or squeeze the nipple, or it may come out on its own.

While your nipple discharge may be harmless, it can sometimes indicate a more serious health issue. Discharge colors and their potential causes may include:

• Bloody nipple discharge: Bloody discharge may happen if you have a papilloma, a harmless wart-like tumor that can grow in the breast. Rarely, this may indicate breast cancer.
• Clear nipple discharge: If clear discharge only comes from one breast, it could be a sign of breast cancer, a papilloma or a blocked nipple duct.
• Green nipple discharge: If you notice green discharge, the most common cause is a breast cyst.
• Yellow discharge from nipple: Cloudy, yellow or pus-like discharge is a common sign of a breast infection.
• White discharge from nipple: Milky-white discharge is often caused by hormonal changes, like pregnancy or stopping breastfeeding.
• Brown nipple discharge: Fibrocystic breast changes or blocked ducts sometimes lead to brown nipple discharge.

If you’re experiencing nipple discharge, a visit to the doctor can give you the answers you need. To diagnose the cause behind your nipple discharge or other related symptoms, your doctor will likely ask you questions about your medical history and perform an exam.

Then, your care team may recommend other tests to gather more information about your health or closely examine your breast tissue. Some standard tests used to diagnose the cause of nipple discharge include blood tests and imaging tests, like a mammogram. The type of tests you need will depend on your breast discharge and other factors unique to your health. 

• Mammogram: A diagnostic mammogram uses X-ray imaging to take pictures of the breasts.
• Ultrasound: A breast ultrasound provides images of the breasts to understand the causes of your nipple discharge. This test sometimes helps identify intraductal papilloma.
• Biopsy: Based on your breast exam or an imaging test, your doctor may use a breast biopsy to take a sample of the tissue in an area of the breast that needs a closer look.
• Blood test: Blood tests give your care team more information about your prolactin levels and thyroid function, which could be causing nipple discharge.