Hyperprolactinaemia (raised prolactin, galactorrhoea)

Endocrinology and metabolism · Abnormal laboratory result · updated 2026-10-30

BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.

Frequency: Cause of 20 to 25% of secondary amenorrhoea ^[1]

Raised prolactin: confirm and look for the cause

Laboratory tests (repeat, at rest, if possible in another laboratory)

Serum prolactin
Serum β-hCG (premenopausal woman)if neededPregnancy is the first cause to rule out ^[1].
TSH (if signs of hypothyroidism)if neededAt least in the presence of signs of hypothyroidism or pituitary hyperplasia on MRI; no demonstrated benefit of routine measurement ^[1].
Serum creatinine with GFR (if renal impairment not known)if neededChronic renal failure raises prolactin; it is usually already known ^[1].
Macroprolactin testing (state on the request)if neededNo gonadal impact, cycle disorders having another cause, normal or doubtful MRI, highly variable measurements ^[1].
IGF-1 (macroadenoma on MRI)if neededFor a macroprolactinoma, look for co-secretion of growth hormone ^[1].
LHif needednon-French guidelineAn American Family Physician review has them measured if hypogonadism is suspected ^[2]. The French consensus takes gonadal impact into account to point toward macroprolactinaemia, without specifying the tests ^[1]. See the page “Testosterone deficiency in men”.
FSHif needednon-French guidelineAn American Family Physician review has them measured if hypogonadism is suspected ^[2]. The French consensus takes gonadal impact into account to point toward macroprolactinaemia, without specifying the tests ^[1]. See the page “Testosterone deficiency in men”.
Total testosteroneif needednon-French guidelineAn American Family Physician review has them measured if hypogonadism is suspected ^[2]. The French consensus takes gonadal impact into account to point toward macroprolactinaemia, without specifying the tests ^[1]. See the page “Testosterone deficiency in men”.
LHif needednon-French guidelineAn American Family Physician review has them measured if hypogonadism is suspected ^[2]. The French consensus takes gonadal impact into account to point toward macroprolactinaemia, without specifying the tests ^[1]. See the page “Secondary amenorrhoea”.
FSHif needednon-French guidelineAn American Family Physician review has them measured if hypogonadism is suspected ^[2]. The French consensus takes gonadal impact into account to point toward macroprolactinaemia, without specifying the tests ^[1]. See the page “Secondary amenorrhoea”.
oestradiolif needednon-French guidelineAn American Family Physician review has them measured if hypogonadism is suspected ^[2]. The French consensus takes gonadal impact into account to point toward macroprolactinaemia, without specifying the tests ^[1]. See the page “Secondary amenorrhoea”.

Detailed explanation and international comparison (in French): read it in English (machine translation)

Do not order

Dynamic tests (TRH, metoclopramide) first-line: unnecessary, and they must not guide the indication for MRI ^[1,3].
Routine catheter placement and multiple samples: not justified, a single resting sample is enough ^[1].
Routine discontinuation of the pill or of menopausal hormone therapy to measure prolactin: not justified in most cases ^[1].
Prolactin measurement during pregnancy, including in a woman followed for microprolactinoma: not recommended ^[1].

On an antipsychotic or another drug raising prolactin

Laboratory tests

Serum prolactin (repeat after stopping or changing the drug if possible)
Serum β-hCG (premenopausal woman)if neededPregnancy remains the first cause to rule out ^[1].

Detailed explanation and international comparison (in French): read it in English (machine translation)

Sources (9)