Galactorrhoea (galactorrhea) is the involuntary spontaneous secretion of milk from both breasts. Discharge can occur between breastfeeding sessions induced by oxytocin reflex () or during weaning.

Galactorrhoea is not necessarily linked to breastfeeding or lactation (); it can occur in men and women through imbalance of prolactin from injuries, infections or tumours in the pituitary gland, other tumours in reproductive organs or as side effects from drug use or medications including contraceptives.

Antonym: Agalactorrhoea

(, 5/7/2021d)

Synonyms: Hyperlactation, milk incontinence, galactorrhea