Characterised by a large amount of milky discharge from multiple ducts.


  • History/examination to consider cause: physiological, drugs, thyroid disorder, pituitary tumour (visual field defects/ new headaches) / prolactinoma (menstrual disturbance/acne)
  • Check serum prolactin/TSH   
    • For serum prolactin the upper end of normal range is 496 mU/L in women and 324mU/L in men
    • Raised prolactin levels are common (e.g. due to higher dose COCP or stress).
    • In prolactinoma a very high value (over 1000 and usually several 1000mU/L) is expected.
  • If a patient has a very high serum prolactin and is not pregnant or breast feeding consider referral to Endocrinology not to breast surgery 


For further information and interpretation of tests see patient.co.uk. The duty biochemist at RCHT can be contacted via switchboard for advice.