Serum Prolactin Level (Mass Concentration)
This test measures the amount of prolactin, a hormone produced by the pituitary gland, in your blood. Prolactin helps regulate breast milk production and affects other bodily functions.
["Prolactin helps control breast milk production and influences reproductive and non-reproductive behaviors."]
Key facts at a glance
- LOINC
- 12835-5
- Short code
- Prolactin 45M p chal SerPl-mCnc
- Synonyms
- Prolactin 45M p chal 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 if you have symptoms like unexplained breast milk production in men, menstrual irregularities, infertility, headaches, or galactorrhea (milk leaking from nipples). It may also be checked to evaluate pituitary gland function or to investigate potential hormonal imbalances.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if instructed by your provider. Bring any medications you’re currently taking, as some may affect results. Avoid smoking or drinking alcohol for a few hours before the blood draw.
What Happens During the Test
A healthcare professional will insert a small needle into a vein in your arm. You may feel a slight pinch, but the procedure is quick. Blood is collected into a tube and sent to the lab for analysis. The test typically takes a few minutes.
What the Results Mean
Results are compared to a general reference range, but individual ranges can vary by lab. High prolactin levels may suggest issues like a pituitary tumor, thyroid problems, or medications that affect hormone production. Low levels might indicate pituitary dysfunction or other hormonal disorders.
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.
◆Associated findings1
Short name
Prolactin
Frequently asked questions
How often should I get this test?
What can affect my prolactin test results?
Do I need to avoid anything before this 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