Prolactin should be measured as part of investigations into loss
of libido, infertility, menstrual disturbances and gynaecomastia.
Prolactin-secreting tumours can present with visual disturbance,
The use of prolactin levels in providing supportive evidence for a
genuinely epilepetic seizure is severely limited by the need for a
sample within 30 minutes of the fit.
Elevated prolactin levels may occur due to (the 5 p's):
Physiological - stress, exercise, lactation, pregnancy
Pharmacological - drugs, especially neuroleptics,
Pituitary - prolactinoma or other tumour causing stalk
Non-Pituitary - PCOS, hypothyroidism, renal failure
Problems - Macroprolactin (non-pathological
increase in apparent prolactin)
Request on ICE
Serum in yellow top (SST) tube
Causes for Rejection
Males: Less than 325 U/L
Females: Less than 500 U/L
Levels of up to twice the reference range may be the result of
The laboratory will automatically investigate samples with
raised prolactin for macroprolactin.