Carbamazepine Serum Concentration (Mass Concentration)
This test measures the amount of carbamazepine, a medication used to treat certain types of seizures and nerve pain, in your blood serum.
["Your doctor may order this test to check if your carbamazepine levels are within the safe range for your treatment."]
Key facts at a glance
- LOINC
- 35599-0
- Short code
- CARB
- Synonyms
- carBAMazepine SerPl Scn-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum separator tube or red-top plain tube (no anticoagulant)
- Units
- N/A
- Ref low
- 4
- Ref high
- 12
- Critical range
- — – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- screen
- CPT
- 80157
- SNOMED
- 387161007
- Specimen volume
- 1-2 mL of serum
- Stability
- Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C): 30 days
- Hemolysis max
- 100
- Lipemia max
- 500
- Icterus max
- 25
- TAT
- 2–8 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may request this test if you’re taking carbamazepine to manage epilepsy or another condition. It helps ensure the drug is working effectively and at a safe level in your body.
What to Expect Before the Test
No special preparation is needed. You’ll typically have a small needle inserted into your arm or vein to draw blood. If you’re on blood thinners, let your doctor know before the test.
What the Results Mean
Results show how much carbamazepine is present in your blood. While reference ranges vary by lab, they help determine if your dose is too high or too low. Your doctor will interpret these results in the context of your treatment plan.
Common Reasons for Monitoring
Regular monitoring helps prevent side effects like dizziness, drowsiness, or rare but serious issues like low blood cell counts. It also ensures the drug remains effective over time.
Reference range
Therapeutic range: 4-12 mcg/mL; Toxic: >15 mcg/mLN/A
No fasting required. Trough levels should be drawn immediately before the next scheduled dose for accurate therapeutic drug monitoring
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Carbamazepine levels can fluctuate due to factors like diet, other medications, or how your body processes the drug. Your doctor may adjust your dose based on these results to balance safety and effectiveness.
Short name
Carbamazepine Level
Frequently asked questions
What happens if my carbamazepine levels are too high?
Can food affect this test?
How often will I need 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 14, 2026. · Read our editorial policy