Platform
Company
Drug Monitoring
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Currently under review
Pending specialist review and validation.
The lithium test measures the amount of lithium circulating in your blood. Lithium is a prescription mood stabilizer used to treat bipolar disorder and, in some cases, to augment treatment for depression. Because the body handles lithium in a narrow range that balances benefit and safety, levels are checked regularly.
A small sample of blood is taken from a vein and analyzed for lithium concentration. Your care team often asks that the sample be drawn just before your next dose, which helps assess the lowest level in your dosing cycle.
Checking your lithium level helps your clinician tailor the dose so you have the best chance of preventing mood episodes while avoiding side effects. The test is ordered when you start treatment, after dose changes, during routine maintenance visits, and whenever you have symptoms that might reflect too much or too little lithium.
Kidney function, salt and fluid balance, and other medicines can strongly affect lithium handling. Monitoring supports safe use, reduces risk of toxicity, and flags situations where closer follow up or additional tests may be needed.
Your result is interpreted against a target range selected for your clinical situation. If the result is lower than expected, your clinician may review the timing of the blood draw, missed doses, and possible drug interactions, and may adjust the dose or recheck the level.
If it is higher than expected, you may be advised to hold or reduce doses, increase fluid intake, or have repeat testing. Seek urgent care if you have concerning symptoms such as severe tremor, vomiting, confusion, or unsteady walking.
Even when your level is stable, you will usually have periodic checks. Your kidney and thyroid function may also be monitored since they influence how your body processes lithium, and monitoring needs can change with age, pregnancy, or other health conditions.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Lithium levels are usually checked as a trough, just before your next dose. Taking a dose shortly before the test can make the result look higher than your usual level.
Dehydration and low dietary salt can increase lithium levels, while sudden increases in salt intake can lower them. Illness with vomiting or diarrhea can also shift levels.
Lithium is cleared by the kidneys. Reduced kidney function, acute illness, or age-related changes can raise levels and increase the risk of side effects.
Common drugs that can increase lithium levels include NSAIDs, ACE inhibitors, ARBs, and some diuretics. Always check with your clinician or pharmacist before adding new medicines.
Switching between immediate release and extended release products, changing brands, or altering dose schedules can change levels. Keep dosing consistent unless your clinician adjusts it.
Body fluid changes and kidney filtration can vary during and after pregnancy, affecting lithium levels. Closer monitoring is often needed in these periods.
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