Nipple discharge: causes, colours, when to see a GP and what tests involve

The NHS says nipple discharge has many possible causes. The common ones it lists are summarised below. The sources read for this guide do not say which are most likely in a given person, because that depends on age, whether you are breastfeeding and the type of discharge, which a clinician will assess.

The NHS describes nipple discharge as liquid that may leak from your nipples on its own or when they are squeezed. It can be lots of different colours, including clear, white, yellow, green or bloody. It is more common if you are pregnant or breastfeeding, but it can affect anyone.

The NHS says it may be nothing serious, but that sometimes it can be a sign of an underlying condition, including a breast cyst or breast cancer. For that reason you should always get it checked, and if it is a sign of breast cancer, finding it early can make it easier to treat.

The NHS’s advice for nipple discharge is to see a GP if you have discharge from either nipple. Its breast lump page also lists bloodstained nipple discharge among unusual changes that should be seen by a GP, along with a nipple turning inwards or dimpled skin. If you are worried about your symptoms, NHS 111 online can help you find support or treatment.

You do not need to wait for other symptoms to appear. Because the cause can be harmless or serious and cannot be told apart reliably by colour alone, the NHS’s advice does not depend on how the discharge looks.

The NHS says nipple discharge is more common if you are pregnant or breastfeeding, and lists pregnancy or breastfeeding as a common cause of leaking from the nipples. But it still says nipple discharge should always be checked, so mention it to your GP, midwife or health visitor rather than assuming it is pregnancy-related.

Mastitis is another cause in breastfeeding women. The NHS describes mastitis as a swollen, hot and painful breast that is most common in breastfeeding women. One of its symptoms is nipple discharge, which may be white or contain streaks of blood, sometimes with flu-like symptoms such as aches, a high temperature and tiredness. The NHS advises seeing a GP if symptoms do not improve 12 to 24 hours after home treatment, or 48 hours after starting antibiotics, or if you get mastitis and are not breastfeeding.

The NHS’s list of symptoms of breast cancer in women includes nipple discharge if you are not pregnant or breastfeeding, which may have blood in it, alongside a lump or swelling in the breast, chest or armpit, skin changes such as dimpling, a change in size or shape, and a nipple turning inwards or developing a rash.

Cancer Research UK says fluid leaking from the nipple when you are not pregnant or breastfeeding can be a sign of breast cancer, but other medical conditions can also cause this. The NHS stresses that having these symptoms does not definitely mean you have breast cancer, but it is important to get checked, and that if symptoms are caused by cancer, finding it early may mean it is easier to treat.

The NHS says the GP will examine your breasts or chest and may refer you to a hospital or breast clinic for further tests. These may include an examination of your breasts or chest, a mammogram (breast X-ray) or an ultrasound scan, and a small sample of cells taken with a needle for testing (biopsy). The tests are often done during the same visit.

The hospital or breast clinic should let you know when and how you will get your results. Some may be available that day, while others, such as a biopsy, can take several weeks. For a breast lump, the NHS says that biopsy results take longer, perhaps about a week. A referral to a breast clinic does not definitely mean you have cancer.

The NHS says treatment depends on what is causing the symptom. For a breast lump it says that most are harmless and may go away on their own without treatment. Infection of the breast would be treated as an infection, and a medicine-related cause would involve a review of the medicine with the prescriber.

If cancer is diagnosed, treatment is planned by a specialist breast team. The sources read for this guide do not cover treatment of breast cancer in detail; the NHS pages on breast cancer in women set out symptoms, tests and treatment.

On the NHS, a GP can refer you to a one-stop breast clinic, where examination, imaging and biopsy are often done in a single visit. Some people choose private breast assessment for a faster appointment, and the tests are broadly the same.

Whichever route you use, ask when you will get results and who will contact you, and keep your GP informed. Regular breast awareness, meaning knowing what is normal for you, helps you notice changes sooner, as the NHS advises.