Serum or plasma concentration of primidone (anticonvulsant metabolite)
This test measures the amount of primidone, a medication used to control seizures, in your blood. Primidone breaks down into other active substances that also help manage seizures.
["Primidone levels help doctors check if your dose is working properly and avoid side effects."]
Key facts at a glance
- LOINC
- 29225-0
- Short code
- Primidone Fld-mCnc
- Synonyms
- Primidone Fld-mCnc
- Category
- chemistry
- 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
Why This Test Matters
Primidone is a prescription medication for epilepsy or seizure disorders. Your doctor may order this test to monitor your blood levels and ensure the medication is effective without causing harmful side effects. Blood levels can change over time due to factors like diet, liver function, or other medications.
How the Test Works
A blood sample is taken from a vein in your arm. The sample is then analyzed using a sensitive laboratory method to measure the concentration of primidone and its active metabolites in your serum or plasma.
What to Expect Before the Test
You may have no preparation needed for this test, but always follow your doctor’s instructions. Avoid eating or drinking anything (except water) for a short period before the blood draw if specified. Wear comfortable clothing with an easy armhole for the blood draw.
What to Expect During the Test
A healthcare professional will insert a small needle into your arm to draw blood. You may feel a slight pinch, but it usually doesn’t cause significant discomfort. The process takes a few minutes, and you can rest while it happens.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Primidone Level
Frequently asked questions
Primidone levels help doctors determine if your medication is at the right dose to control seizures without causing toxicity. Low levels may indicate insufficient medication, while high levels could signal side effects like dizziness, drowsiness, or liver issues. Regular monitoring is especially important if you’re taking other medications that interact with primidone.
How often should I get this test?
What are the possible side effects of primidone?
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