Serum or plasma concentration of primidone (anticonvulsant metabolite)
This test measures the amount of primidone, a medication used to control certain types of seizures, in your blood.
["Primidone levels help doctors monitor your dose and ensure it stays within safe ranges for seizure control."]
Key facts at a glance
- LOINC
- 97153-1
- Short code
- Primidone Ur Ql Cfm
- Synonyms
- Primidone Ur Ql Cfm
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- confirm
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test if you’re taking primidone (brand names like Mysoline) to manage epilepsy or other seizure disorders. Regular monitoring helps prevent side effects and ensures the medication works effectively.
What to Expect Before the Test
No special preparation is needed. You may have a small needle inserted into your arm or vein for blood collection, which usually takes a few minutes. If you’re taking primidone, your doctor may schedule tests during steady-state dosing (typically 7–10 days after starting or adjusting the dose).
What the Results Mean
Results are compared to a general reference range for primidone, but exact values depend on your lab and medical context. Low levels may indicate insufficient medication, while high levels could signal toxicity or improper metabolism.
Common Causes of Abnormal Results
Factors like liver disease, certain medications (e.g., carbamazepine), or alcohol use can affect primidone metabolism, leading to higher or lower-than-expected levels. Always discuss all medications and health conditions with your healthcare provider.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Primidone levels are critical for balancing seizure control and side effects. Therapeutic ranges (typically 4–12 mcg/mL) are guidelines, not absolute rules, and may vary by patient. Your doctor will adjust your dose based on these results and your clinical response.
Short name
Primidone level
Frequently asked questions
Why do doctors check primidone levels regularly?
What happens if my primidone level is too high?
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