What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• Having a lot of emotional stress or doing strenuous exercise before the test.
• Trouble sleeping. Prolactin levels are highest during sleep so if you do not sleep well, your levels may be lower than normal.
• Stimulating your nipples.
• Taking certain medicines, such as birth control pills, high blood pressure medicines, tricyclic antidepressants, or medicines for mental illness, such as phenothiazines.
• Using cocaine.
• Having a test with radioactive tracer a week before the prolactin test.

What To Think About

• Men and nonpregnant women normally have low levels of prolactin. The only known problem caused by a lack of prolactin is not being able to make milk after pregnancy. Therefore, even people who have an abnormally low level of prolactin are not treated for the condition.
• Men may have a prolactin test if a man lacks sexual desire or if he has a hard time having an erection (erectile dysfunction). Prolactin levels may be checked when a man's testosterone levels are really low. For more information, see the topic Testosterone.
• Treatment for a pituitary gland tumor that is making too much prolactin includes medicines (such as bromocriptine), removing the pituitary gland, or radiation therapy to the gland. The choice of treatment is based on the size of the tumor and the health and age of the person being treated.