Serum Prolactin Level
This test measures the amount of prolactin, a hormone produced by your pituitary gland, in your blood. Prolactin helps regulate breast milk production and influences other bodily functions.
Prolactin levels can signal potential hormonal imbalances or conditions affecting your reproductive or endocrine health.
Key facts at a glance
- LOINC
- 25739-4
- Short code
- Prolactin 30M p 200 ug TRH IV SerPl-mCnc
- Synonyms
- Prolactin 30M p 200 ug TRH IV SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 2
- Ref high
- 18
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84146
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend a prolactin test to check for conditions like hyperprolactinemia (high prolactin levels), which can cause issues such as infertility, irregular menstrual cycles, or galactorrhea (milk production outside breastfeeding). It may also be used to evaluate symptoms like headaches, vision changes, or unexplained weight gain that could relate to pituitary gland problems.
What to Expect Before the Test
No special preparation is needed for this blood test. You may have fasting instructions depending on your provider’s protocol, but typically, you can eat and drink normally. On the day of the test, avoid smoking and limit caffeine intake to avoid potential fluctuations in hormone levels.
What Happens During the Test
A healthcare professional will draw blood from a vein in your arm using a small needle. You may feel a slight pinch, but it usually doesn’t cause significant discomfort. The process takes a few minutes, and you can resume normal activities afterward.
What the Results Mean
Results are interpreted by your healthcare provider based on your symptoms, medical history, and other test results. High prolactin levels may indicate conditions like pituitary tumors, certain medications (e.g., antidepressants or antipsychotics), or thyroid issues. Low levels might suggest rare pituitary disorders or other hormonal imbalances.
Reference range
Adult males: 2-18 ng/mL; Females: 2-29 ng/mLN/A
For females: inform if menstrual cycle status. For certain tests, timing within menstrual cycle may matter.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated prolactin levels can interfere with normal hormone function, leading to fertility problems, menstrual irregularities, or symptoms related to pituitary gland dysfunction. It’s important to discuss any persistent symptoms or abnormal test results with your doctor to explore potential causes and treatment options.
Short name
Prolactin
Frequently asked questions
How long does it take to get my prolactin test results?
Can I take anything to lower my prolactin levels before the test?
What are common symptoms that might lead to a prolactin test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy