Calcitonin, Serum/Plasma — 5 Minutes After 0.5 mcg/kg Pentagastrin IV, Mass Concentration
Measures blood calcitonin 5 minutes after intravenous pentagastrin, which stimulates thyroid C cells and is used to evaluate possible C-cell disease.
["This timed blood test measures calcitonin after stimulation to help evaluate thyroid C-cell disorders, especially medullary thyroid carcinoma."]
Key facts at a glance
- LOINC
- 1376-3
- Short code
- Calcit 5M p 0.5 ug/kg Pg IV SerPl-mCnc
- Synonyms
- Calcit 5M p 0.5 ug/kg Pg IV SerPl-mCnc
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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
What is this test?
This test measures the concentration of calcitonin in serum or plasma. Calcitonin is produced by thyroid C cells, and this version is collected 5 minutes after pentagastrin is given intravenously to stimulate C-cell secretion.
Why might I need this test?
A provider may use this test when there is concern for medullary thyroid carcinoma, thyroid C-cell hyperplasia, or another condition that increases calcitonin production. A stimulated measurement can sometimes reveal C-cell activity that is not clearly elevated without stimulation.
How is the test performed?
Pentagastrin is administered by intravenous injection under medical supervision, and blood is collected at the specified time, 5 minutes later. The laboratory measures the calcitonin concentration in the serum or plasma sample.
How do I prepare for the test?
Follow your healthcare provider's instructions about fasting, medications, and the timing of the test. Because pentagastrin is given and a precisely timed blood sample is required, this test should be completed in a supervised clinical setting.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated or unusually strong rise in calcitonin after stimulation may indicate increased thyroid C-cell activity, including medullary thyroid carcinoma or C-cell hyperplasia. Results must be interpreted with the baseline measurement, the stimulation protocol, imaging, and other clinical findings. A low result does not by itself exclude all thyroid C-cell disease.
Short name
Pentagastrin-Stimulated Calcitonin
Frequently asked questions
What does calcitonin measure?
Why is pentagastrin used?
Is this the same as a routine thyroid blood 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.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy