Tacrolimus concentration in blood (2-hour post-dose)
This test measures the amount of tacrolimus, a medication used to prevent organ rejection after a transplant, in your blood 2 hours after you took your dose. It helps doctors check if your dose is working properly.
["This test helps ensure your transplant medication is at the right level for safety and effectiveness."]
Key facts at a glance
- LOINC
- 92729-3
- Short code
- Tacrolimus 2h p Bld-mCnc
- Synonyms
- Tacrolimus 2h p Bld-mCnc
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your doctor may order this test if you’re taking tacrolimus to manage organ rejection after a transplant. It helps monitor whether your medication is keeping your immune system from attacking your new organ. This test is especially important if you’re on a strict dosing schedule or if your levels might fluctuate due to other health conditions.
What Does This Test Tell You?
The result tells your healthcare team how much tacrolimus is in your blood at a specific time. Low levels might mean your dose isn’t working well, while high levels could increase your risk of side effects. Your doctor will use these results to adjust your medication if needed.
How Is This Test Performed?
A small blood sample is taken from a vein, usually in your arm. The sample is then sent to a lab for analysis using a specialized method to measure tacrolimus levels accurately.
What Do My Results Mean?
Your results will be compared to guidelines specific to your situation (like transplant type, other medications, or health status). Your doctor will explain what the numbers mean in the context of your care plan.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is critical for transplant patients because tacrolimus levels must be carefully balanced. Too little can lead to organ rejection, while too much can cause serious side effects like kidney damage or infections. Regular monitoring helps prevent these risks and ensures your treatment stays effective.
Short name
Tacrolimus 2-hour blood level
Frequently asked questions
Why do I need this test every few weeks?
What if my results are too high or too low?
Can I eat or drink before this 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