Carbamazepine Peak Concentration (Serum/Plasma)
This test measures the highest blood level of carbamazepine, a medication used to treat certain types of seizures or nerve pain. It helps doctors monitor how well your body is processing the drug over time.
["This test helps ensure your carbamazepine levels stay within safe ranges for your condition."]
Key facts at a glance
- LOINC
- 97190-3
- Short code
- CARBPEAK
- Synonyms
- carBAMazepine Peak SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (serum) or SST (serum separator tube); plasma may be collected in green-top (lithium heparin) or lavender-top (EDTA) tube
- 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
- Immunoassay (e.g., PETINIA, EMIT, FPIA) or LC-MS/MS
- CPT
- 80156
- SNOMED
- 395077007
- Specimen volume
- 1-2 mL serum or plasma
- Stability
- Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C): 30 days
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 1–8 hours
- Order
- routine
Why This Test Matters
Carbamazepine is a medication that works by stabilizing electrical activity in the brain. Too much or too little can affect its effectiveness or cause side effects. Your doctor may order this test to check how your body is handling the drug, especially if you’ve had changes in your dose or symptoms.
What to Expect Before the Test
No special preparation is needed for this test. You’ll provide a blood sample, usually drawn from a vein in your arm. The process is quick and painless, and you can resume normal activities afterward.
What the Results Mean
Peak levels indicate the highest concentration of carbamazepine in your blood after you’ve taken your dose. This helps doctors assess whether your medication is working as intended and whether you need adjustments to your dose.
Common Uses
This test is often used in people taking carbamazepine for epilepsy or neuropathic pain to ensure therapeutic drug levels are maintained. It may also be used if you’re experiencing side effects like dizziness, drowsiness, or rash, which could signal unsafe levels.
Reference range
Therapeutic range: 4.0-12.0 mg/L (trough). Peak levels are typically drawn 2-4 hours after oral dose and may be higher than trough levels.N/A
No special preparation required. Patient should take medication as prescribed; peak sample should be drawn at the appropriate time after dose (typically 2-4 hours post-dose for immediate-release, 4-8 hours for extended-release formulations).
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Carbamazepine Peak Level
Frequently asked questions
What causes carbamazepine levels to be tested?
How often should this test be done?
What happens if my peak level is too high or too low?
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