Prolactin, Serum
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 body functions, including reproduction.
["Prolactin levels can help diagnose hormonal imbalances or conditions affecting milk production."]
Key facts at a glance
- LOINC
- 50517-2
- Short code
- Prolactin sp1 SerPl-mCnc
- Synonyms
- Prolactin sp1 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 Is This Test Done?
Your healthcare provider may order a prolactin test to check for conditions like hyperprolactinemia (too much prolactin), pituitary tumors, or issues with hormone regulation. It may also be used to monitor treatment for conditions like breast cancer or infertility.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if instructed. Wear comfortable clothing and plan to stay for about 15 minutes while the blood is drawn.
What Happens During the Test?
A healthcare professional will insert a small needle into a vein in your arm or hand to collect a blood sample. You may feel a slight pinch, but it usually doesn’t cause significant discomfort. The blood will be sent to a lab for analysis.
What Are Possible Results?
Results are interpreted by your provider based on your medical history, symptoms, and other tests. High or low prolactin levels may signal underlying health concerns that need further evaluation.
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 cause symptoms like missed periods, infertility, breast tenderness, or galactorrhea (milk leakage). Low levels may be linked to conditions like hypothyroidism or certain medications. Your provider will discuss findings in the context of your health.
Short name
Prolactin Level
Frequently asked questions
What causes prolactin levels to be too high?
How long does it take to get results?
Can diet or exercise affect prolactin levels?
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