Serum Prolactin Level (Quantitative)
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 help diagnose hormonal imbalances or conditions affecting your pituitary gland."]
Key facts at a glance
- LOINC
- 44929-8
- Short code
- Prolactin 15M p TRH IV SerPl-aCnc
- Synonyms
- Prolactin 15M p TRH IV SerPl-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85610
- SNOMED
- 396252006
- 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 to check for conditions like hyperprolactinemia (high prolactin levels), which can cause issues with fertility, menstrual problems, or other hormonal symptoms. It may also be used to evaluate symptoms such as headaches, vision changes, or unexplained galactorrhea (milk production outside of pregnancy). Sometimes, it’s part of a broader evaluation for pituitary disorders or tumors.
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 your doctor specifies it. Wear comfortable clothing for blood drawing. If you’re taking medications that affect prolactin (like certain antidepressants or antipsychotics), let your doctor know beforehand.
What Happens During the Test?
A healthcare provider will draw blood from a vein in your arm using a small needle. You may feel a brief pinch, but the procedure is quick. The blood sample is then sent to a lab for analysis.
What the Results Mean
Results are compared to standard reference ranges, but they can vary by lab. High prolactin levels may suggest pituitary tumors, thyroid issues, or certain medications. Low levels might indicate conditions like hyperthyroidism or pregnancy. Your doctor will discuss the results in the context of your symptoms and medical history.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Prolactin
Frequently asked questions
What Causes Abnormal Results?
How Often Should I Get This Test?
Can I Take Anything Before 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