Prolactin blood test
Prolactin is a hormone released by the pituitary gland. The prolactin test measures the amount of prolactin in the blood.
How the Test is Performed
A fasting blood sample is needed.
Blood sample is needed
Venipuncture is the collection of blood from a vein. It is most often done for laboratory testing.
Read Article Now Book Mark ArticleHow to Prepare for the Test
No special preparation is necessary.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
Why the Test is Performed
Prolactin is a hormone released by the pituitary gland. The pituitary is a small gland at the base of the brain. It regulates the body's balance of many hormones.
Prolactin stimulates breast development and milk production in women. There is no known normal function for prolactin in men.
Prolactin is usually measured when checking for pituitary tumors and the cause of:
- Breast milk production that is not related to childbirth (galactorrhea)
- Decreased sex drive (libido) in men and women
- Erection problems in men
Erection problems in men
An erection problem occurs when a man cannot get or keep an erection that is firm enough for intercourse. You may not be able to get an erection at ...
Read Article Now Book Mark Article - Not able to get pregnant (infertility)
Infertility
Infertility means you cannot get pregnant (conceive). There are 2 types of infertility:Primary infertility refers to couples who have not become preg...
Read Article Now Book Mark Article - Irregular or no menstrual periods (amenorrhea)
Amenorrhea
Absence of a woman's monthly menstrual period is called amenorrhea. Primary amenorrhea is when a girl has not yet started her monthly periods, and sh...
Read Article Now Book Mark Article
Normal Results
The normal values for prolactin are:
- Men: less than 20 ng/mL (425 µg/L)
- Nonpregnant women: less than 25 ng/mL (25 µg/L)
- Pregnant women: 80 to 400 ng/mL (80 to 400 µg/L)
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
People with the following conditions may have high prolactin levels:
- Chest wall injury or irritation
- Presence of nipple rings
- Disease of an area of the brain called the hypothalamus
Hypothalamus
The hypothalamus is an area of the brain that produces hormones that control:Body temperatureHeart rateHungerMoodRelease of hormones from many glands...
Read Article Now Book Mark Article - Thyroid gland does not make enough thyroid hormone (hypothyroidism)
Hypothyroidism
Hypothyroidism is a condition in which the thyroid gland does not make enough thyroid hormone. This condition is often called underactive thyroid....
Read Article Now Book Mark Article - Kidney disease
- Pituitary tumor that makes prolactin (prolactinoma)
- Other pituitary tumors and diseases in the area of the pituitary
- Abnormal clearance of prolactin molecules (macroprolactin)
Certain medicines can also raise prolactin level, including:
- Antidepressants
- Butyrophenones
- Estrogens
- H2 blockers
- Methyldopa
- Metoclopramide
- Opioid medicines
- Phenothiazines
- Reserpine
- Risperidone
- Verapamil
Marijuana products can also raise prolactin level.
If your prolactin level is high, the test may be repeated in the early morning after an 8-hour fast.
The following can temporarily increase prolactin levels:
- Emotional or physical stress (occasionally)
- High-protein meals
- Intense breast stimulation
- Recent breast exam
- Recent exercise
Interpretation of an abnormally high prolactin blood test is complicated. In most case, your provider will need to refer you to an endocrinologist, a doctor who specializes in hormone problems.
Risks
There is little risk in having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include:
- Excessive bleeding
- Multiple punctures to locate veins
- Fainting or feeling lightheaded
- Hematoma (blood buildup under the skin)
- Infection (a slight risk any time the skin is broken)
Reviewed By
Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Chernecky CC, Berger BJ. Prolactin (human prolactin, HPRL) - serum. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:910-911.
Guber HA, Oprea M, Rusell YX. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 25.
Kaiser U, Ho K. Pituitary physiology and diagnostic evaluation. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 8.