Prolactin, Serum (Plasma) by Immunoassay
This test measures the amount of prolactin, a hormone produced by your pituitary gland, in your blood. Prolactin helps regulate breast milk production and affects other body functions like mood and reproduction.
["Prolactin levels can help diagnose hormonal imbalances or conditions affecting your pituitary gland."]
Key facts at a glance
- LOINC
- 12827-2
- Short code
- Prolactin sp6 p chal SerPl-mCnc
- Synonyms
- Prolactin sp6 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 Is This Test Done?
Your doctor may order a prolactin test if you have symptoms like unusual breast milk production (galactorrhea), irregular menstrual periods, infertility, headaches, or vision problems. It may also be checked during evaluations for pituitary tumors, thyroid disorders, or other hormonal issues.
What to Expect Before the Test
No special preparation is 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. Avoid smoking or caffeine before the test if your doctor advises it.
What Happens During the Test?
A healthcare provider will insert a needle into a vein in your arm or hand to collect a blood sample. You may feel a slight pinch or discomfort, but it usually lasts only a few seconds. The blood is then sent to a lab for testing.
What Are Possible Results?
Results are typically reported in nanograms per deciliter (ng/dL). High prolactin levels may suggest pituitary tumors, thyroid issues, or medications affecting hormone production. Low levels could indicate rare pituitary 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.
Elevated prolactin levels often point to conditions like prolactinomas (benign pituitary tumors), thyroid disorders (hypothyroidism), or certain medications (e.g., antipsychotics). Low levels are less common but may signal pituitary damage or genetic disorders. Regular monitoring helps manage symptoms and prevent complications.
Short name
Prolactin Level
Frequently asked questions
How often should I get this test?
What can affect my prolactin test results?
Do I need to take any special steps after the 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