Nipple discharge, medically termed galactorrhea when it is milky and unrelated to recent pregnancy or breastfeeding, is a common symptom that often causes alarm. Fluid leaking from the breast can be a sign of hormonal fluctuations or a response to physical stimulation. However, it always warrants investigation to rule out underlying medical conditions.
The Direct Link: Stress and Hormonal Changes
Chronic psychological stress measurably impacts the endocrine system. The primary response involves the Hypothalamic-Pituitary-Adrenal (HPA) axis, which coordinates the release of stress hormones like cortisol. Cortisol prepares the body for “fight or flight,” and its activation influences other hormonal pathways.
A related pathway involves prolactin, the hormone responsible for milk production. Stress is a known factor that stimulates prolactin release from the pituitary gland. This occurs because neurochemicals released during the stress response can override the constant inhibition of prolactin normally maintained by dopamine.
When stress causes a temporary elevation in prolactin levels, it can lead to galactorrhea. This is a physiological response stemming from normal body function under duress, and is not a sign of disease. The discharge is typically bilateral (from both breasts) and is often only expressed when the nipple is squeezed or stimulated.
Common Non-Stress Related Causes
While stress can be a factor, nipple discharge is more frequently caused by non-stress-related issues. One common category is physical stimulation, where repeated friction from tight clothing, excessive self-examination, or sexual activity triggers the nerves around the nipple. This signal travels to the brain, causing a temporary release of prolactin, similar to the initial stages of breastfeeding.
Many medications interfere with hormonal balance and can induce discharge. Certain antipsychotic drugs, which block dopamine receptors, can inadvertently raise prolactin levels because dopamine normally suppresses this hormone. Other common culprits include some blood pressure medications, hormonal birth control pills, and specific antidepressants.
Systemic health problems, particularly those involving the endocrine system, can also be responsible. Hypothyroidism, an underactive thyroid gland, can lead to increased prolactin secretion because the attempt to increase thyroid hormones also stimulates prolactin release. Benign tumors in the pituitary gland, called prolactinomas, directly produce excess prolactin and are a significant cause of galactorrhea.
Identifying When Medical Attention Is Required
Although nipple discharge is often benign, certain characteristics must prompt an immediate visit to a healthcare provider for a thorough evaluation. The most concerning characteristic is unilateral discharge, meaning the fluid is coming from only one breast. Discharge that is bloody, clear, or persistent should also be investigated promptly.
Another important red flag is discharge that occurs spontaneously, leaking without any squeezing or stimulation of the nipple. Any discharge accompanied by localized symptoms, such as a new lump, fever, or changes to the nipple skin like scaling or inversion, requires urgent medical assessment. A professional must rule out more serious underlying conditions, such as ductal issues or, in rare cases, malignancy.