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What Causes Clear or Bloody Nipple Discharge? Your Symptoms Explained

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Breast discharge can be caused by normal and abnormal hormonal changes. Pregnancy and breastfeeding are normal hormonal changes that can cause milky nipple discharge. Cancerous and non cancerous breast conditions can also cause discharge from the nipples. Read now for more information on causes and treatment options.

7 most common causes

Breast Abscess
Prolactinoma
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Breast Cancer
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Breastfeeding Complications
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Fibrocystic breast changes
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High prolactin hormone level
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Intraductal papilloma

Nipple discharge quiz

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Nipple discharge symptoms

Discharge from one or both nipples, called galactorrhea, can be alarming, but it is usually not a sign of a serious medical condition. The characteristics of discharge will vary based on the underlying cause. A detailed description of the color, when the discharge occurs, and accompanying symptoms will allow your physician to determine whether tests and imaging are needed.

Common characteristics of nipple discharge

If you're experiencing nipple discharge, it can likely be described by:

  • Color: It may be bloody, clear, milky, yellow, or black.
  • Onset: Discharge may occur spontaneously or only when pinching the nipple.
  • Unilateral or bilateral: Discharge may come from just one or both nipples.
  • Location: Discharge may come from a single location on the nipple or from multiple spots.

Common accompanying symptoms

If you're experiencing nipple discharge, it's likely to also experience:

Nipple discharge causes

The following details may help you better understand your symptoms. If your nipple discharge persists or becomes worrisome due to other symptoms, see a physician.

Normal hormonal changes

An elevated level of prolactin, the hormone that stimulates lactation, can cause the production of breast milk.

  • Pregnancy: Increased levels of estrogen in pregnancy can cause milky nipple discharge.
  • Breastfeeding: After delivering a baby, milk is produced and released from the nipples to allow breastfeeding.

Abnormal hormonal changes

Certain medical conditions and medications can cause elevated prolactin in the absence of pregnancy or breastfeeding. In addition to causing nipple discharge, high prolactin commonly causes menstruation to stop.

  • Thyroid disorders: An abnormally low level of thyroid hormone can indirectly lead to high prolactin levels. Other possible symptoms of low thyroid hormone include constipation, fatigue and constantly feeling cold.
  • Pituitary tumor: A tumor in the pituitary gland in the brain can cause increased prolactin levels. This condition can be associated with headaches and decreased peripheral vision.
  • Medication side effect: Certain medications cause a decrease in dopamine, which normally inhibits prolactin. As a result, prolactin increases and stimulates milky nipple discharge. Antipsychotic medications commonly have this side effect. In addition, some antidepressants and antihypertensives can also cause galactorrhea.
  • Chronic medical conditions: Liver or kidney disease can cause elevated prolactin, leading to milky nipple discharge.
  • Chest wall abnormalities: Injury, infection, or surgery of the chest wall can cause abnormal signaling that results in high prolactin and nipple discharge.

Breast conditions

The following breast conditions may result in nipple discharge.

  • Benign breast problems: Abnormalities, such as growths or blockages, of one or more of the ducts that transport milk to the surface of the nipple can cause discharge. Changes in the breasts around the time of menstruation can also cause nipple discharge.
  • Breast infection: An infection can cause nipple discharge filled with pus. The breasts are particularly vulnerable to infection during breastfeeding. Typically, there will also be redness and pain.
  • Breast cancer: Rarely, nipple discharge can be a sign of cancer in the breast. In this case, the discharge will be present on just one side with other symptoms such as a mass or a rash on the nipple.

5 nipple discharge conditions

The list below shows results from the use of our quiz by Buoy users who experienced nipple discharge. This list does not constitute medical advice and may not accurately represent what you have.

Nipple discharge quiz

Take a quiz to find out what's causing your discharge.

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Prolactinoma

A prolactinoma is abnormal growth of the cells that produce the hormone prolactin in the pituitary gland, a small endocrine gland at the base of the brain. Prolactinoma leads to hyperprolactinemia or excess levels of prolactin in the bloodstream. Prolactinomas can occur in men or women but are more common in women of childbearing age.

Common symptoms in women include amenorrhea (absence of a menstrual period), infertility and nipple discharge. Symptoms in men include decreased libido, erectile dysfunction, infertility, breast tissue enlargement, and rarely, nipple discharge. Additionally, because the prolactinoma occurs at the base of the brain, it can cause headaches or vision changes.

Prolactinomas can be treated with medications to lower the prolactin levels, with surgery to remove the tumor, or with radiation.

Physiologic breast discharge

Physiologic breast discharge is any fluid that comes out of the nipple area in your breast.

You should visit your primary care physician to evaluate the discharge and discuss treatment options.

Rarity: Uncommon

Top Symptoms: nipple discharge, randomly leaking fluid from the breast

Symptoms that never occur with physiologic breast discharge: breast lump

Urgency: Primary care docto

Non-specific breast pain

Nonspecific breast pain, also called mastalgia or mastodynia, refers to tenderness or pain in the breast with no obvious cause. It almost always proves to have a benign (non-cancerous) cause.

Breast pain is most common in women aged 35 to 50 and still experiencing menstruation. Fibrocystic changes are common in this age group, where tiny, fluid-filled sacs form within breast tissue and might be felt as small, tender, but non-cancerous lumps.

Birth control pills, hormone replacement therapy, caffeine, and soy can cause breast tenderness in women of any age. A breast infection can cause painful lumps.

A medical provider should be seen, in order to rule out any serious condition and get treatment for the discomfort.

Diagnosis is made through patient history; physical examination; mammogram or breast ultrasound; and sometimes biopsy.

A breast infection will be treated with antibiotics. Large, painful cysts may have the fluid drained or be surgically removed. Lifestyle improvements regarding diet and exercise are often helpful, as well as adjustments to birth control pills or hormone therapy.

Intraductal papilloma

Breast problems such as lumps are very common and often not caused by breast cancer. An intraductal papilloma is such a benign breast lump situated in the milk ducts.

All new breast lumps should be examined by a doctor to determine if further testing is needed, so the best thing to do is to make an appointment with your primary care physician.

Rarity: Uncommon

Top Symptoms: breast lump, painful breast lump, painless breast lump, white or clear fluid leaking from the breast, nipple lump

Symptoms that never occur with intraductal papilloma: armpit lump

Urgency: Primary care doctor

High prolactin hormone level

Hyperprolactinemia means the pituitary gland secretes too much prolactin, the hormone responsible for producing milk in a new mother. The condition can appear in both women and men.

It can be caused by pregnancy; by an ovulatory disorder; by some psychiatric medications; or by a prolactin-secreting tumor of the pituitary (prolactinoma.)

Women with other reproductive disorders, such as polycystic ovary syndrome (PCOS,) are most susceptible. Hyperprolactinemia is also seen in those with hypothyroidism and chronic renal failure. Many patients on hemodialysis have elevated prolactin levels.

Symptoms in both women and men include reduced libido (sex drive) and infertility. Men may show breast enlargement and women may develop breast milk.

If not treated, hyperprolactinemia can result in loss of bone density in both women and men.

Diagnosis is made through blood testing to measure hormone levels, and sometimes MRI of the pituitary gland underneath the brain.

Treatment may include "watchful waiting," or a period spent observing the symptoms to see if they change; drug therapy; or surgery.

Rarity: Rare

Top Symptoms: headache, vaginal bleeding, irregular period, decreased sex drive, enlargement of breasts

Urgency: Primary care doctor

Fibrocystic breast changes

Fibrocystic change is a generalized term used to describe a variety of benign changes in the breast. Symptoms of this condition are breast swelling or pain, as well as nodules, lumpiness, or nipple discharge.

You should visit your primary care physician to evaluate the lump. Diagnosis typically just involves a physical exam and imaging. A biopsy would be needed in case scarier things need to be ruled out, but it's not always necessary. Treatment of a cyst involves aspirating the contents of the cyst, a mass just needs a biopsy with no further treatment, and nipple discharge doesn't require treatment.

Breast cancer

Breast cancer has several names, depending on the part of the breast where it starts:

  • Lobular carcinoma affects the milk glands.
  • Ductal carcinoma affects the milk ducts.
  • Sarcoma affects the connective tissue.
  • Paget's Disease affects the nipple and areola.

Women over age 50 with a family history of the disease, and/or certain genetic factors, are most at risk, but anyone can get breast cancer at any age. It is rare in men but does occur.

Symptoms include a lump, thickening, or pain anywhere in the breast or armpit; red, flaky, or irritated breast or nipple skin; nipple discharge; and any area of irregular skin or misshapenness.

Many harmless conditions can cause similar signs, so it is important to see a medical provider about any of these symptoms.

Diagnosis is made through physical examination; imaging such as ultrasound, mammogram, or MRI; and sometimes biopsy.

Treatment involves a combination of surgery, radiation therapy, and chemotherapy.

The best prevention is a combination of screening mammograms as recommended by the medical provider, and monthly self-examination.

Breast abscess

Breast abscess is a complication of mastitis, which is an inflammation of the breast tissue. An abscess is a pocket of pus that forms within the breast, usually just under the skin.

Most susceptible are women who are breastfeeding. Bacteria can be transferred into the milk ducts from the skin or from the infant's mouth. Women not breastfeeding can be infected through a sore nipple or from a nipple piercing.

If a milk duct is blocked through trauma, compression, or incomplete emptying, bacteria can gain a foothold and an abscess can form.

The abscess forms a hot, reddened, painful lump in the breast. There will be flu-like symptoms of fever, chills, fatigue, and body aches.

Diagnosis is made through physical examination and sometimes a milk sample.

Treatment is with antibiotics along with rest, fluids, and over-the-counter pain relievers. Unless otherwise directed by the medical provider, it is safe to continue nursing the baby. If the abscess persists, it may be drained under local anesthesia with a needle and syringe.

Nipple discharge quiz

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Nipple discharge treatments and relief

Most cases of nipple discharge do not require urgent evaluation. A breast infection is one exception, however, since the infection can spread to the rest of the body.

At-home treatments

Home treatments may help with nipple discharge, such as the following.

  • Wear loose clothing and avoid stimulating the nipples
  • Cover the nipples with pads: This can prevent clothes from getting stained or wet.
  • If you are breastfeeding: You should continue to breastfeed and make sure your breasts drain completely.
  • Warm compresses

When to see a doctor

Persistent nipple discharge, especially among other symptoms, may require tests and imaging. Make an appointment with your physician if:

  • You recently started a new medication
  • Your nipple discharge is present only on one side
  • You notice a mass in the breast
  • Your discharge appears spontaneously, without squeezing the nipples
  • You have bloody or clear discharge

Medical treatments

Your physician may prescribe one or more of the following treatments, depending on the cause of your nipple discharge:

  • Stopping a medication that may be responsible
  • Decrease prolactin levels: Likely with a new medication.
  • Address a thyroid disorder: Likely with a new medication.
  • Antibiotics and/or drainage to treat a breast infection
  • Referral to a surgeon: This is if a tumor in the breast or pituitary gland has been discovered on imaging.

When it is an emergency

Seek emergency nipple discharge treatment if:

  • You have rapidly progressing redness, pain, and warmth of the breast
  • You have a fever and chills

FAQs about nipple discharge

Can hormones cause nipple discharge?

Elevated prolactin levels cause milk production in the breasts, leading to nipple discharge. This occurs as a normal part of pregnancy and breastfeeding. Medical conditions that cause a high level of the prolactin can lead to milky nipple discharge. In some cases, the high prolactin is caused by changes in other hormones, such as estrogen and thyroid hormone.

What causes breasts to leak when not pregnant?

Several medical conditions can cause milk production when you are not pregnant or breastfeeding. These include hypothyroidism (low levels of thyroid hormone), pituitary tumors, and liver or kidney disease. Some medications can also cause milk production as a side effect.

Why is there a clear discharge from my breast when squeezed?

Nipple discharge that only occurs with squeezing is usually normal. However, you should see a physician if the discharge comes from only one breast, if it continues without stimulation, if you notice a mass, or if the discharge becomes bloody or straw-colored.

Why do I have nipple discharge before my period?

Nipple discharge can occur as part of the fibrocystic breast changes that happen before menstruation in some people. In this case, the discharge will likely be bilateral and dark in color, and the breasts will become tender and lumpy.

Why do I discharge from one nipple?

Discharge from only one nipple is likely caused by a process occurring only in that breast. Possible causes include a breast infection, blockage of a duct, or a type of benign growth called intraductal papilloma. Rarely, discharge from just one nipple can be a sign of breast cancer. Unilateral nipple discharge should be evaluated by a medical provider.

Questions your doctor may ask about nipple discharge

  • Has anyone in your family had cancer?
  • Do you currently smoke?
  • When was your last menstrual period?
  • What color is your discharge?

Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.

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Dr. Rothschild has been a faculty member at Brigham and Women’s Hospital where he is an Associate Professor of Medicine at Harvard Medical School. He currently practices as a hospitalist at Newton Wellesley Hospital. In 1978, Dr. Rothschild received his MD at the Medical College of Wisconsin and trained in internal medicine followed by a fellowship in critical care medicine. He also received an MP...
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References

  1. Leung AKC, Pacaud D. Diagnosis and Managment of Galactorrhea. Am Fam Physician. 2004 Aug 1;70(3):543-550. AAFP Link
  2. Kosir MA. Nipple Discharge. Merck Manual Consumer Version. Updated July 2018. Merck Manuals Consumer Version Link
  3. Barry M. Nipple Discharge. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Chapter 175. NCBI Link
  4. Sajadi-Ernazarova KR, Adigun R. Breast, Nipple Discharge. [Updated 2018 Oct 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2018 Jan-. NCBI Link
  5. Parthasarathy V, Rathnam U. Nipple discharge: an early warning sign of breast cancer. Int J Prev Med. 2012;3(11):810-4. NCBI Link