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Lithium (Li) Unit Converter
Lithium (Li) is a monovalent cation used as a mood stabilizer, primarily in the treatment of Bipolar Disorder. Due to its very narrow therapeutic index (the difference between the effective dose and the toxic dose), plasma concentrations must be carefully monitored via Therapeutic Drug Monitoring (TDM). [Image of lithium ion’s therapeutic range]
Lithium is cleared almost entirely by the kidneys. Factors affecting renal clearance (like dehydration or use of certain diuretics) can lead to rapid accumulation and toxicity. Clinically, concentrations are reported in mEq/L (milliequivalents per liter) or mmol/L. Since Li+ is monovalent, these two units are numerically interchangeable.
SI Units / Activity
RecommendedMillimoles/Milliequivalents per liter (1:1 conversion).
Mass Equivalents
Clinical Context
Therapeutic Range: 0.6 – 1.2 mEq/L (or mmol/L).
Toxic Threshold: > 1.5 mEq/L. Symptoms of toxicity include severe tremor, diarrhea, confusion, and eventual renal failure. TDM typically requires blood draws 12 hours after the last dose. The mass conversion relies on MW 6.94 g/mol: 1 mmol/L ≈ 0.694 mg/dL.
Clinical References
How to Use This Calculator
Follow these steps to get accurate clinical conversions instantly.
Enter Values
Input your laboratory results into the corresponding unit field (e.g., mEq/L). You can use either dot or comma decimals.
Automatic Conversion
The calculator works in real-time. Conversions cover molarity (mmol/L) and mass (mg/dL).
Verify Units
Note that mmol/L and mEq/L are numerically identical for lithium.
Reset
Use the Clear button to reset all fields before starting a new calculation.
Frequently Asked Questions & Tips
Yes. Since Lithium is a monovalent ion (Z = 1), the milliequivalent concentration equals the millimolar concentration.
Lithium levels must be drawn 12 hours after the last dose (a “trough” level) for accurate TDM and comparison against the therapeutic range.