locator iconlocator icon
All Labs
add to cart

Prolactin Test (PRL)

Interpreting Results
Prolactin Test

Overview of PRL

What is PRL?

Prolactin is a hormone produced by the Pituitary gland which is situated at the base of the brain. Prolactin is normally produced in both males and non-pregnant females in small amounts. The main function of this hormone is to stimulate milk production (lactation) after childbirth, so, it is also known as the milk-producing hormone. The levels of prolactin hormone are generally high during pregnancy and after childbirth. But, high levels of prolactin can also be seen in many disease conditions in both men and women. The prolactin test measures the levels of prolactin in the blood, to check and monitor the associated disease condition.

Why is PRL done?

  • To investigate the cause of abnormal breast milk discharge (galactorrhea), menstrual irregularities or infertility in non-pregnant women

  • To evaluate the role of prolactin in case of lactation failure in women after childbirth

  • To investigate the cause of erection problems, testicular failure or abnormal breast discharge in men

  • To investigate the cause of loss of sex drive (libido) in both men and women

  • To detect and monitor the progress of prolactinoma (tumor of the pituitary gland that causes high levels of prolactin) in both men and women

What does PRL Measure?

The prolactin (PRL) test measures the levels of prolactin in blood. The prolactin hormone is produced by the pituitary gland which is located at the base of the brain. The primary function of this hormone is to help in lactation i.e. production of milk after childbirth. Prolactin levels are usually high during pregnancy and after childbirth. During pregnancy, this hormone along with other hormones like estrogen and progesterone stimulates the breasts for milk production. After the childbirth, it helps to maintain the breast milk production. Suckling of the breasts by the baby is important for the release of prolactin hormone. If a woman stops breastfeeding, the level of prolactin hormone will return to normal.

Abnormally high levels of prolactin are seen in certain disease conditions like prolactinoma (non-cancerous tumor of the pituitary gland) in men and women. It is generally benign (non-cancerous) in nature and is seen more commonly in women. If the tumor is quite large, it can put pressure on the optic nerve and the patient may present with headache and visual disturbances.

Preparation for PRL

  • Blood sample should be collected 4 hours after waking.

Sample Type for PRL

The sample type collected for Prolactin Test is: Blood

Interpreting PRL results


High levels of prolactin can be seen in:

  • Tumors of the pituitary gland that produces and releases prolactin (Prolactinoma)

  • Diseases of the hypothalamus (a gland located in the brain)

  • Kidney disease

  • Liver disease

  • Hypothyroidism

  • Polycystic ovary disease (PCOD)

  • Conditions like anorexia nervosa (eating disorder)

Low levels of prolactin can be seen in:

  • Pseudohypoparathyroidism

  • Patients taking bromocriptine

  • Pituitary deficiency like necrosis or infarction of the pituitary gland

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about PRL

Frequently Asked Questions about Prolactin Test

Q. Are there any precautions required to be followed before the prolactin test?
The blood sample is collected 4 hours after waking up as the levels of Prolactin hormone are at the peak immediately after waking up. Inform your doctor if you are taking any medicines including herbals or any over the counter (OTC) medicines as they may interfere with your test values.
Q. Which medicines can affect the levels of Prolactin hormone?
Certain drugs can decrease the levels of Prolactin, such as Dopamine (used in conditions like shock), Levodopa (used for Parkinson’s disease) or Ergot alkaloid derivatives (used for severe headaches). Certain drugs can cause elevated levels of Prolactin, such as CNS depressants, Estrogen, drugs used for the treatment of hypertension like Reserpine, Verapamil, Methyldopa and drugs used for treating gastroesophageal reflux like cimetidine.
Q. Are there any other conditions which can alter the levels of Prolactin?
Yes, there are other conditions in which high levels of prolactin can be seen, for eg., lung cancer, seizures, trauma to the chest wall, stress due to illness and use of Marijuana.
Q. The test results showed high prolactin levels. Do I require any other tests?
When the prolactin levels are high, the doctor may advise you to get Follicle stimulating hormone (FSH) test, Luteinizing hormone (LH) levels to assess fertility problems. The testosterone test is advised in males when the prolactin level is found high. The doctor may also advise for MRI scan for the diagnosis of prolactinoma.
Q. I got my Prolactin levels tested. Now, my doctor has advised me thyroid test. Why is it so?
In many patients, high levels of Prolactin are seen along with low levels of thyroid hormones (hypothyroidism), so you may be asked to get your thyroid tests done. However, high levels of Prolactin does not cause low levels of thyroid hormones.
Q. What is prolactinoma?
Prolactinomas are tumors of the pituitary gland which are usually benign (non-cancerous) in which there is a production of high amounts of prolactin. These are more common in women as compared to men. Prolactinomas may cause menstrual irregularities, infertility and bone loss in women and erectile dysfunction, gynecomastia (breast enlargement), decreased muscle mass and bone loss in men. If the size of the tumor is quite large, it can cause pressure symptoms like headache and vision problems.
Q. How is this test performed?
This test is performed on a blood sample. A syringe with a fine needle is used to withdraw blood sample from a blood vessel in your arm, generally from the inner side of the elbow area. The doctor, nurse or the phlebotomist will tie an elastic band around your arm which will help the blood vessels to swell with blood. This makes it easier to withdraw blood. You may be asked to tightly clench your fist. Once the veins are clearly visible, the area is cleaned with an antiseptic solution. The needle is then inserted into the blood vessel to collect the sample. You may feel a tiny pinprick during the procedure. Blood sample, once collected, is then sent to the laboratory.
Q. Is there any risk associated with this test?
There is no risk associated with the test. However, since this test involves a needle prick to withdraw the blood sample, in very rare cases, a patient may experience increased bleeding, hematoma formation (blood collection under the skin), bruising or infection at the site of needle prick.
Q. Are there any foods which can increase the levels of prolactin?
Yes, foods such as barley (jau), fennel (saunf) and fenugreek (methi) seeds, oats, whole wheat, brown rice and papaya can increase the levels of prolactin. These foods are considered to be helpful in milk production in new mothers.
Q. Are there any foods which can decrease the levels of prolactin?
Yes, foods rich in vitamin B6 like bananas, potatoes, chicken, spinach and foods rich in zinc like beef, turkey, beans, shellfish and its supplements can decrease the prolactin levels.
+ more

Provided By




About Thyrocare Laboratories

Thyrocare Technologies Limited is India's first and most advanced Totally Automated Laboratory having its strong presence in more than 2000 cities / towns in India and internationally. Thyrocare is India's first fully automated diagnostic laboratory with a focus on providing quality at affordable costs to laboratories and hospitals in India and other countries. Thyrocare operates with a Centralized Processing Laboratory (CPL) in Mumbai - India for esoteric tests; and Regional Processing Laboratory in major metro cities of India and other parts of Asia. We have focus on strong technologies, strong brands and strong systems that enable all laboratories to give their clients the best of science and technology at an affordable cost. With a belief that 'Quality' is the heart of any intelligent management, Thyrocare became one of the first Indian diagnostic laboratories to obtain internationally renowned quality accreditations like ISO 9001-2000 rating as early as 2001, which is now escalated to ISO 9001:2008; NABL (National Accreditation Board for Testing and Calibration Laboratories) in 2005 and CAP (College of American Pathologists) certification in 2007.

User Reviews about Prolactin Test

Sheetal Singhvi
Service was very excellent
Best service. On time delivery if reports. They did what they said.

Available at Other Labs