Galactorrhoea in Singapore: Milky Discharge Explained

Written & reviewed by the BestDoctors.sg editorial team · Last updated 25 Aug 2026 · General information, not medical advice

Milky discharge with new headaches or vision changes (especially loss of side vision) can signal a pituitary tumour and needs prompt assessment. Any bloody, single-duct or one-sided discharge, or a lump, must be checked to exclude cancer — do not assume it is “just hormonal.”

What it is

Galactorrhoea reflects raised prolactin or increased breast sensitivity to it. Anything that pushes prolactin up, or interferes with the brain’s normal dopamine “brake” on prolactin, can trigger it. Because it is a symptom of an underlying process, assessment focuses on identifying that cause rather than on the discharge alone.

Causes and risk factors

Medicines are a common cause, including some antipsychotics and antidepressants, anti-sickness drugs, some blood-pressure medicines, opioids and oestrogen or hormonal treatments — these are named as classes only, and you should never stop or change a prescribed medicine without the prescriber. An underactive thyroid can raise prolactin, as can a prolactinoma (a usually benign pituitary tumour), nipple or breast stimulation, chest-wall injury or shingles, some herbal supplements, and chronic kidney disease. In some people no cause is found (idiopathic), thought to relate to breast tissue being more sensitive to normal prolactin levels.

Symptoms

The main feature is milky, or sometimes yellow or green-tinged, discharge from one or both breasts, often from several ducts, that may leak on its own or with squeezing. Associated features can point to the cause: raised prolactin can cause irregular, infrequent or absent periods, reduced fertility and low libido (and in men reduced libido or breast enlargement); a pituitary tumour can cause headaches and vision problems, classically loss of side vision; and a thyroid cause can bring tiredness, weight gain and feeling the cold.

Red flags

Galactorrhoea with headaches or visual disturbance, especially loss of peripheral vision, needs prompt assessment, as this combination can signal a pituitary tumour, and a sudden severe headache with vision change warrants urgent care. Separately, bloody or single-duct or one-sided discharge, or a breast lump, is not typical galactorrhoea and must be assessed to exclude breast cancer — do not assume any bloody or one-sided discharge is just hormonal. See a doctor for milky discharge that is persistent or unexplained, or that comes with period changes, fertility problems or symptoms of an underactive thyroid. A sudden severe headache with collapse or sudden vision loss is a 995 situation.

How it is assessed and treated

Assessment includes a history and examination with a careful review of medicines and supplements and questions about periods, headaches and vision, plus blood tests for prolactin, thyroid function and a pregnancy test, with kidney function and other hormones checked as needed; a single mildly raised prolactin is often repeated, since stress or recent nipple stimulation can transiently raise it. Breast imaging (ultrasound with or without mammogram) is done if the discharge is bloody, one-sided or single-duct or there is a lump, and an MRI of the pituitary and formal visual-field testing are arranged if a pituitary tumour is suspected. Treatment addresses the underlying cause: a prescriber may review, switch or adjust a responsible medicine (never stopped abruptly on your own); treating an underactive thyroid often resolves it; a prolactinoma is usually managed with prolactin-lowering medicines, with surgery only occasionally needed; and nipple-stimulation or idiopathic cases are managed with reassurance once serious causes are excluded. This guide names medicines only as examples and gives no doses.

What it means for periods and fertility

Because raised prolactin can disturb the menstrual cycle, galactorrhoea sometimes comes with irregular or absent periods and reduced fertility, which understandably worries women planning a pregnancy. The reassuring point is that treating the underlying cause — adjusting a medicine, correcting the thyroid, or lowering prolactin from a prolactinoma — often restores normal cycles and fertility, so it is well worth getting assessed rather than living with it. Persistent galactorrhoea with normal tests and no bothersome symptoms may simply be monitored after breast cancer and other causes are excluded, and reducing unnecessary nipple stimulation — from frequent self-checking, friction from clothing, or vigorous breast stimulation — can help settle it. If a prolactinoma is the cause, it is worth knowing that these tumours usually respond well to medication that both lowers prolactin and can shrink the tumour, so treatment often addresses the discharge, the periods and the tumour together.

When to see a doctor

See a doctor for any unexplained milky discharge not linked to pregnancy or breastfeeding, and promptly if there are headaches or vision changes, period or fertility changes, or symptoms of thyroid problems. Seek assessment — not reassurance — for any bloody, one-sided or single-duct discharge or a lump, to exclude cancer.

Related breast-health topics

• Fibrocystic breast changes
• Intraductal papilloma
• Breast abscess
• Breast calcifications
• Mammary duct ectasia
• Phyllodes tumour
• Breast self-examination
• Inverted nipple
• Fat necrosis of the breast
• Breast cancer screening
• Breast surgeons in Singapore
• Breast Pain and Nipple Discharge in Singapore: Causes and When to Worry

Sources

• You & Your Hormones (Society for Endocrinology) — Prolactinoma: yourhormones.info
• NHS — Nipple discharge: nhs.uk
• Mayo Clinic — Galactorrhea: mayoclinic.org
• Breast Cancer Foundation Singapore: bcf.org.sg