At what level is lithium considered toxic?

Lithium is a medication commonly used to treat bipolar disorder, and it requires monitoring of serum levels to ensure patient safety and efficacy. The therapeutic range for lithium is typically 0.6 to 1.2 mEq/L. Levels above this therapeutic range indicate increasing toxicity, with serious effects becoming apparent as levels rise.

When levels exceed 2.0 mEq/L, the risk of toxicity significantly increases. At this point, patients may start experiencing symptoms such as nausea, vomiting, diarrhea, and tremors. Severe toxicity can lead to more serious complications, including ataxia, confusion, and even seizures or renal failure at levels above this threshold.

Therefore, lithium levels over 2.0 mEq/L are classified as toxic, necessitating urgent medical evaluation and intervention to prevent severe adverse effects. Observing this threshold is crucial in managing patients on lithium therapy to ensure their safety.