Unexpected breast milk production, known medically as galactorrhea, involves the discharge of milky fluid from the nipples when an individual is not pregnant or actively breastfeeding. While often benign, galactorrhea is a symptom that warrants medical evaluation to identify its underlying cause. It indicates a possible imbalance or condition within the body.
What Is Galactorrhea?
Galactorrhea refers to the secretion of breast milk or a milk-like fluid from the nipples, unrelated to childbirth or nursing. The discharge can vary in appearance, ranging from white and milky to clear or yellowish. It may spontaneously leak from one or both breasts, or it might only appear when the breast or nipple is stimulated. While lactation is a normal physiological process during and after pregnancy, galactorrhea occurs outside of these expected circumstances. This condition can affect individuals of any sex or age, though it is more frequently observed in women, particularly those of reproductive age.
Underlying Causes of Unexplained Lactation
The unexpected production of breast milk often stems from hormonal regulation. Elevated prolactin levels, known as hyperprolactinemia, are a common cause. Prolactin is the hormone primarily responsible for milk production. This increase can result from conditions affecting the pituitary gland, a small gland at the base of the brain that produces prolactin.
Pituitary tumors, specifically noncancerous prolactinomas, are a frequent cause of hyperprolactinemia. These tumors can produce excess prolactin or interfere with signals that suppress its release. Other medical conditions leading to galactorrhea include an underactive thyroid gland (hypothyroidism), where elevated thyroid-releasing hormone (TRH) stimulates prolactin. Chronic kidney and liver disease can also contribute by affecting the body’s ability to clear hormones, leading to increased prolactin.
Certain medications are known to induce galactorrhea as a side effect. These include some antidepressants, antipsychotics, blood pressure medications, and opioids. These drugs can interfere with dopamine, a neurotransmitter that normally inhibits prolactin release. Physical stimulation of the breasts, such as frequent self-examinations, tight clothing, or sexual activity, can also stimulate prolactin release and lead to discharge.
Less common causes include nerve damage to the chest wall from injuries, surgery, or conditions like shingles. Some herbal remedies and supplements, such as fenugreek and fennel, have also been associated with galactorrhea due to their effects on hormone levels. Stress can also play a role by influencing hormonal regulation. In some instances, no clear cause is identified, referred to as idiopathic galactorrhea, which may suggest heightened breast tissue sensitivity to normal prolactin levels.
When to Consult a Doctor
It is advisable to seek medical attention if breast discharge is persistent, occurs spontaneously without nipple stimulation, or involves only one breast. If the discharge is bloody, clear, or yellowish, or if it is accompanied by other concerning symptoms, a medical consultation is important. These accompanying symptoms might include headaches, vision changes, irregular or absent menstrual periods, unexplained weight fluctuations, or persistent fatigue.
Preparing for a doctor’s visit can help facilitate an accurate diagnosis. Bring a comprehensive list of all medications, including over-the-counter drugs, supplements, and herbal remedies, as well as any recent changes in overall health or new symptoms. Discussing the frequency, appearance, and triggers of the discharge can provide valuable information for the medical professional.
Diagnosing and Addressing the Cause
Diagnosing the cause of galactorrhea typically involves a thorough medical evaluation. A healthcare provider will perform a physical examination, including a breast exam, to assess the discharge and check for any breast abnormalities. Blood tests are often conducted to measure hormone levels, particularly prolactin and thyroid-stimulating hormone (TSH), to identify any imbalances. A pregnancy test is also usually performed to rule out pregnancy as the cause of lactation.
If elevated prolactin levels are detected, or if other symptoms suggest a pituitary issue, imaging studies such as a magnetic resonance imaging (MRI) scan of the brain may be recommended to check for pituitary tumors. Once the underlying cause is identified, treatment focuses on addressing that specific condition. This might involve adjusting or discontinuing medications that are contributing to the discharge, managing an underlying medical condition like a thyroid disorder with appropriate medication, or, in cases of prolactinomas, using medications like cabergoline or bromocriptine to lower prolactin levels and shrink the tumor.