Lithium Serum/Plasma Concentration Over 24 Hours (Rate of Change)
This test measures how quickly your lithium levels change over a 24-hour period in your blood. It helps doctors assess how well your medication is being managed.
["Understanding how lithium levels fluctuate can help prevent dangerous spikes or drops."]
Key facts at a glance
- LOINC
- 3722-6
- Short code
- Lithium Cl 24h Ur+SerPl-vRate
- Synonyms
- Lithium Cl 24h Ur+SerPl-vRate
- 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 Is Done
Your healthcare provider may order this test if you’re taking lithium (a medication often used to treat conditions like bipolar disorder or severe depression) and want to check how your body is responding over time. It’s particularly useful if you’re experiencing side effects or if your medication levels aren’t stable.
What to Expect Before the Test
No special preparation is needed. You’ll have a small needle inserted into your arm or vein to draw blood. If you’re taking lithium, your provider may ask you to stop it temporarily before the test, so results aren’t affected by the medication.
What the Results Mean
This test doesn’t provide a single number but tracks changes in your lithium levels over 24 hours. Your results will be compared to how your body typically responds to lithium. Rapid changes might indicate issues like poor kidney function or improper dosing.
Common Causes of Abnormal Results
High or unstable lithium levels could be due to dehydration, kidney problems, or incorrect dosing. Low levels might suggest your medication isn’t working as intended or you’re missing doses. Always discuss any symptoms with your doctor.
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 fluctuate too much can increase the risk of side effects like nausea, tremors, or long-term damage to organs. Doctors use this test to adjust medication carefully to keep levels safe and effective.
Short name
Lithium Rate of Change (24h)
Frequently asked questions
Will I need to stop taking lithium before this test?
How long will it take to get my results?
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