Prolactin, Serum (Mass Concentration)
This test measures the amount of prolactin, a hormone produced by the pituitary gland, in your blood. Prolactin helps regulate milk production and affects other bodily functions.
["Prolactin levels can help diagnose hormonal imbalances or conditions affecting the pituitary gland."]
Key facts at a glance
- LOINC
- 50520-6
- Short code
- Prolactin sp4 SerPl-mCnc
- Synonyms
- Prolactin sp4 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 Might You Need This Test?
Your doctor may order a prolactin test if you have symptoms like unusual breast milk production, irregular menstrual periods, infertility, headaches, or signs of a pituitary tumor. It may also be used to monitor treatment for certain hormonal disorders or conditions like hyperprolactinemia.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to avoid certain medications or activities that could affect results, such as smoking or certain supplements. Your doctor will provide specific instructions if applicable.
How the Test Is Performed
A blood sample is taken from a vein, typically in your arm, using a small needle. You may feel a slight pinch when the needle goes in, but it usually doesn’t cause much discomfort. The sample is then sent to a lab for analysis.
What the Results Mean
Results are compared to a reference range, which can vary slightly between labs. High prolactin levels may indicate conditions like pituitary tumors, thyroid issues, or certain medications. Low levels might suggest pituitary damage 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.
◆Associated findings1
Short name
Prolactin Level
Frequently asked questions
What causes prolactin levels to be high?
How long does it take to get the results?
Can I take anything before my 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