This is the technical term for the flow of milk from the breasts. It is usually reserved for describing the inappropriate secretion of milk, ie when not breastfeeding or pregnant.
The main cause is the excess production of prolactin , particularly if both breasts are secreting milk. Prolactin is a hormone secreted by the pituitary gland which stimulates the production of milk in the breasts.
Certain drugs can cause galactorrhoea eg tranquillisers, the oral contraceptive pill, methadone.
Unilateral (one-sided) galactorrhoea and/or blood stained discharge could indicate local breast disease.
Other causes include pituitary disease, renal disease, an underactive thyroid gland and sarcoid.
You should see your doctor if you think you have galactorrhoea. Usually, no serious cause is found.
This article published on
28 November 2005
Next review date 01/11/2013
Contraception and pregnancy