A nurse is reviewing routine laboratory values for several clients who are taking lithium carbonate. Which of the following clients should the nurse assess further for findings indicating lithium toxicity?

ideation, as some clients express relief anticipating death. While concerning, it is less specific than other indicators, as it may not always reflect serotonin-driven despair or intent, requiring further assessment to confirm risk.

Choice B reason: Feeling overwhelmed by simple tasks indicates severe depression, linked to serotonin and prefrontal cortex dysfunction, impairing executive function. This heightens suicidal risk, as cognitive overload and hopelessness increase impulsivity and despair, making it a critical neurobiological marker requiring immediate intervention to prevent self-harm.

Choice C reason: Calling family to make amends signals high suicidal risk, often reflecting intent to resolve relationships before death, driven by serotonin dysregulation and prefrontal cortex deficits. This behavior indicates advanced planning, a neurobiological marker of serious ideation, necessitating urgent safety measures to prevent completion.

Choice D reason: An abrupt mood improvement can indicate suicidal risk, as it may reflect relief from deciding to end life, linked to serotonin and dopamine shifts. This neurobiological change reduces despair temporarily, increasing energy for action, making it a critical warning sign requiring immediate assessment and intervention.

Choice A reason: Valproic acid does not typically require thyroid function tests, as it primarily affects liver metabolism via glucuronidation and mitochondrial pathways. Thyroid dysfunction is not a common side effect, unlike with lithium, which impacts thyroid hormone synthesis. This instruction is irrelevant, as valproic acid’s toxicity risks are hepatic, not thyroid-related.

Choice B reason: Expecting a gradual decrease in valproic acid dosage is incorrect, as it is titrated to therapeutic levels for conditions like seizures or bipolar disorder, based on serum levels (50–100 mcg/mL). Dosage adjustments depend on efficacy, not routine reduction, as stable neural excitability is needed, making this scientifically inaccurate.

Choice C reason: Taking aspirin for pain with valproic acid is risky, as both inhibit platelet function, increasing bleeding risk via synergistic effects on prostaglandin synthesis. Valproic acid’s hepatic metabolism also raises hepatotoxicity concerns, making aspirin inappropriate. Alternative analgesics like acetaminophen are safer, rendering this instruction incorrect.

Choice D reason: Valproic acid requires regular liver function monitoring, as it is hepatically metabolized and can cause hepatotoxicity, particularly in the first 6 months, due to mitochondrial dysfunction and oxidative stress. Elevated liver enzymes or rare fulminant hepatitis necessitate early detection to prevent liver failure, making this a critical instruction.