Lithium Concentration (Serum or Plasma)
This test measures the amount of lithium, a medication used to treat certain mental health conditions, in your blood.
["Your lithium level helps doctors monitor your medication dose and prevent potential side effects."]
Key facts at a glance
- LOINC
- 4300-0
- Short code
- Lithium Dose
- Synonyms
- Lithium Dose
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.6
- Ref high
- 1.2
- Critical range
- — – 1.6 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
Lithium is prescribed to manage conditions like bipolar disorder or severe depression. Keeping your levels within the right range is crucial to avoid both underdosing (which may not work well) and overdosing (which can be dangerous). Your doctor will order this test to check how your body is handling the medication and adjust your dose if needed.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for a few hours before the test if it’s done in the morning. Bring a list of all medications, including over-the-counter drugs and supplements, to share with your healthcare provider.
What Happens During the Test
A healthcare professional will draw blood from a vein in your arm. The process is quick and typically causes only mild discomfort. The blood sample is then sent to a lab for testing.
What the Results Mean
Results are usually reported as a concentration in milligrams per deciliter (mg/dL). Your doctor will interpret the results in relation to your symptoms, medical history, and current medications. They may recommend follow-up tests if your levels are too high or too low.
Reference range
Therapeutic: 0.6-1.2 mmol/LN/A
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.
Lithium levels that are too low may mean your medication isn’t working effectively, while levels that are too high can lead to serious health risks, including kidney damage, seizures, or even coma. Regular monitoring helps prevent these issues and ensures your treatment remains safe and effective.
Short name
Lithium Level
Frequently asked questions
How often should I get this test?
What happens if my lithium level is too high?
Can I drink alcohol 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 17, 2026. · Read our editorial policy