Prolactin, Serum (Plasma) by Immunoassay
This test measures the level of prolactin, a hormone produced by the pituitary gland that plays a role in breast milk production and regulates certain reproductive functions.
["Prolactin levels help diagnose hormonal imbalances or conditions affecting the pituitary gland."]
Key facts at a glance
- LOINC
- 12825-6
- Short code
- Prolactin sp4 p chal SerPl-mCnc
- Synonyms
- Prolactin sp4 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 to check for conditions like hyperprolactinemia (high prolactin levels), which can affect fertility, menstrual cycles, or cause symptoms like breast tenderness or missed periods. It may also be used to evaluate symptoms such as headaches, vision changes, or unexplained infertility.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to avoid certain medications or activities (like smoking or exercise) for a few hours before the test. If you’re taking medications that affect prolactin levels, let your healthcare provider know.
What Happens During the Test?
A healthcare professional will draw blood from a vein in your arm. You may feel a slight pinch, but it’s generally quick and not painful. The blood sample is then sent to a lab for testing.
What Are Possible Results?
Results are compared to standard reference ranges, but your actual values will be interpreted by your doctor based on your medical history and symptoms.
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.
High prolactin levels may indicate conditions like pituitary tumors, thyroid disorders, or certain medications (e.g., antidepressants, antipsychotics). Low levels could suggest pituitary damage or other hormonal imbalances. Always discuss results with your doctor for personalized guidance.
Short name
Prolactin
Frequently asked questions
What causes prolactin levels to be abnormally high?
How long does it take to get the results?
Can lifestyle changes 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