Skip to content

Serum/plasma concentration of carbamazepine (mass concentration)

Published: August 9, 2026Updated: August 17, 2026

This test measures the amount of carbamazepine, a medication used to control certain types of seizures, in your blood.

Quick summary

["Helps monitor your carbamazepine dose for safety and effectiveness."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
57808-8
Short code
HEDIS 2010-13 MPM-E carBAMazepine
Synonyms
HEDIS 2010-13 MPM-E carBAMazepine
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
4
Ref high
12
Critical range
— – 15 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

Why This Test Is Done

Your healthcare provider may order this test if you’re taking carbamazepine to manage epilepsy or nerve pain. It helps ensure the right dose is working properly and checks for potential side effects, such as toxic levels that could cause dizziness, nausea, or confusion.

How the Test Works

A blood sample is taken from a vein in your arm. The lab uses a sensitive method (likely high-performance liquid chromatography or immunoassay) to measure carbamazepine levels in your serum or plasma.

What to Expect Before the Test

No special preparation is usually needed, but inform your provider if you’re taking other medications, have liver or kidney issues, or are pregnant. Avoid eating or drinking for 2 hours before the test if instructed.

What the Results Mean

Results are compared to a general reference range, though individual ranges may vary based on your health and dose. Low levels might mean the medication isn’t working as intended, while high levels could signal toxicity.

Reference range

Therapeutic: 4-12 mcg/mLN/A

Specimen: serum

No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Carbamazepine Level

Frequently asked questions

How often should I get this test?
Your provider will determine the timing based on your treatment plan, but it’s often done every few weeks or months to check how your body is responding to the medication.
What if my results are outside the normal range?
If levels are too high, your doctor may reduce your dose or switch medications. If levels are too low, they may increase your dose or check for interactions with other drugs.
Does diet or exercise affect carbamazepine levels?
Dietary changes or exercise alone won’t directly alter carbamazepine levels, but they can influence how your body processes the medication. Always follow your provider’s guidance on lifestyle and medication timing.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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 17, 2026. · Read our editorial policy