A nurse is caring for a client who takes lithium for bipolar disorder and has a lithium level of 2.3 mEq/L. Which of the following findings should the nurse expect to observe?

Choice A reason: Gastrointestinal upset—including nausea, vomiting, and diarrhea—is a hallmark sign of lithium toxicity, especially when levels exceed 2.0 mEq/L. These symptoms often appear early and may precede more severe neurological manifestations. At a level of 2.3 mEq/L, the client is experiencing moderate to severe toxicity, and GI symptoms are expected. Choice B reason: Severe hypertension is not typically associated with lithium toxicity. Lithium more commonly causes hypotension or orthostatic changes due to fluid and electrolyte imbalances. Hypertension would suggest another etiology and is not a direct effect of elevated lithium levels. Choice C reason: Fine hand tremors are seen at therapeutic levels of lithium and are considered a common side effect. However, at toxic levels, tremors may become coarse and more pronounced, along with other neurological signs such as confusion and ataxia. Choice D reason: Large output of dilute urine may occur in chronic lithium use due to nephrogenic diabetes insipidus, but it is not a reliable indicator of acute toxicity. In toxicity, renal function may be impaired, and urine output may actually decrease.