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Nipple Discharge


Lydia Choi

, MD, Karmanos Cancer Center

Reviewed/Revised Jan 2024
Topic Resources

Nipple discharge can occur in women who are not pregnant or breastfeeding, especially during the reproductive years. Nipple discharge is not necessarily abnormal, even among postmenopausal women, although it is always abnormal in men. Spontaneous unilateral nipple discharge, regardless of color, is considered abnormal.

Nipple discharge can be serous (yellow), mucinous (clear and watery), milky, sanguineous (bloody), purulent, multicolored and sticky, or serosanguineous (pink). It may occur spontaneously or only in response to breast manipulation.

Pathophysiology of Nipple Discharge

Nipple discharge may be breast milk or an exudate produced by a number of conditions.

Breast milk production in nonpregnant and nonlactating women (galactorrhea Prolactinoma Prolactinomas are noncancerous tumors made up from lactotrophs in the pituitary gland. The most common symptom of a prolactinoma is galactorrhea. Diagnosis is by measurement of prolactin levels... read more ) typically involves an elevated level of prolactin, which stimulates glandular tissue of the breast. However, only some patients with elevated prolactin levels develop galactorrhea.

Etiology of Nipple Discharge

Most frequently, nipple discharge has a benign cause (see table ). Cancer (usually intraductal carcinoma or invasive ductal carcinoma) causes < 10% of cases. The rest result from benign ductal disorders (eg, intraductal papilloma, mammary duct ectasia, fibrocystic changes Etiology Etiology ), endocrine disorders (eg, pituitary tumor), liver disorders, breast abscesses or infections, or use of certain drugs. Of these causes, intraductal papilloma is probably the most common; it is also the most common cause of a bloody nipple discharge without a breast mass.


Evaluation of Nipple Discharge


History of present illness should include the following:

Review of systems should seek symptoms suggesting possible causes, including the following:

Nonlactational mastitis may be periductal mastitis, idiopathic granulomatous mastitis, or tuberculous mastitis.

Past medical history should include possible causes of hyperprolactinemia, including chronic renal failure, pregnancy, liver disorders, and thyroid disorders, as well as history of infertility, hypertension, depression, breastfeeding, menstrual patterns, and cancer. Clinicians should ask specifically about drugs that can cause prolactin release such as oral contraceptives, antihypertensive drugs (eg, methyldopa, reserpine, verapamil), H2-antagonists (eg, cimetidine, ranitidine), opioids, and dopamine D2 antagonists (eg, many psychoactive drugs, including phenothiazines and tricyclic antidepressants).

Physical examination

Physical examination focuses on the breast examination Evaluation Breast symptoms (eg, masses, nipple discharge, pain) are common, accounting for millions of medical visits every year. Although the great majority of symptoms have benign causes, breast cancer... read more Evaluation . In male patients, gynecomastia Gynecomastia This photo shows enlarged breast tissue in a male patient. Gynecomastia is hypertrophy of breast glandular tissue in males. It must be differentiated from pseudogynecomastia, which is increased... read more Gynecomastia , if present, is noted. The breasts are inspected for symmetry, dimpling of the skin, erythema, swelling, color changes in the nipple and skin, and crusting, ulceration, or retraction of the nipple. The breasts are palpated for masses and evidence of lymphadenopathy in the axillary or supraclavicular region. If there is no spontaneous discharge, the area around the nipples is systematically palpated to try to stimulate a discharge and to identify any particular location associated with the discharge.

A bright light and magnifying lens can help assess whether the nipple discharge is uniductal or multiductal.

Red flags

Interpretation of findings

If a mass is present or discharge is guaiac-positive, even if bilateral, cancer must be considered.

Discharge that is bilateral and/or multiductal and guaiac-negative suggests an endocrine cause.

Presence of any of the following requires follow-up with a surgeon who is experienced with breast disorders:

  • A breast mass

  • A bloody (or guaiac-positive) discharge

  • A spontaneous unilateral discharge

  • History of an abnormality on a mammogram or a breast ultrasound

For other suggestive findings, see table .


If endocrine causes are suspected, the following are measured:

  • Prolactin level

  • Thyroid-stimulating hormone (TSH) level

If discharge is guaiac-positive, the following is done:

  • Cytology

If there is a palpable breast mass, evaluation may include

  • Ultrasonography, cyst aspiration, or mammography

If there is no mass but cancer is otherwise suspected or if other tests are indeterminate, the following is done:

  • Mammography

If results of imaging or cytology (of cyst aspirate) are abnormal, image-guided biopsy is done.

If mammography and ultrasonography do not identify a source and the discharge is spontaneous and comes from a single duct or breast, evaluation may include

  • Ductography (contrast-enhanced imaging of the milk duct) or image-guided biopsy

Treatment of Nipple Discharge

Treatment of a nipple discharge is based on the cause. If imaging identifies a lesion, core needle biopsy is done.

Breast cancer is treated as appropriate.

Intraductal papillomas, which are the most common cause of bloody nipple discharge, can be excised after diagnosis with needle biopsy. This procedure prevents further nipple discharge and rules out the small possibility of a coexisting cancer. Symptomatic, palpable papillomas or those with associated atypia should be excised. Incidentally discovered papillomas do not require excision.

Hyperprolactinemia is treated with drugs or surgical removal of a pituitary tumor. Liver disorders are treated as appropriate for the specific disorder.

Key Points

  • Nipple discharge is most often benign.

  • Bilateral, multiductal, guaiac-negative discharge is usually benign and has an endocrine etiology.

  • Spontaneous, unilateral discharge requires diagnostic testing; this type of discharge may be cancer, particularly if it is bloody (or guaiac-positive).

  • Presence of a breast mass, a bloody (or guaiac-positive) discharge, or history of an abnormality on a mammogram or an ultrasound scan requires follow-up with a surgeon who is experienced with breast disorders.

Drugs Mentioned In This Article

Drug Name Select Trade
Calan, Calan SR, Covera-HS, Isoptin, Isoptin SR, Verelan, Verelan PM
Acid Reducer, Major Acid Reducer, Tagamet, Tagamet HB
Acid Reducer, Ranitidine, Taladine, Zantac, Zantac EFFERdose, Zantac Maximum Strength, Zantac Solution, Zantac Syrup
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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