Table 2. Summary of Published Case Reports of Hyponatremia in Patients With Schizophrenia Who Were Taking Second-Generation Antipsychotic Medications

Case	Sex	Age, Years	Event	Outcome	Suspected Drug	Comments	Recommendation
Bachu et al, 2006¹⁵	Male	60	Hyponatremia SIADH	Recovery	Aripiprazole	Hyponatremia was attributed to aripiprazole, and the diagnosis of SIADH was made based on clinical and laboratory results.	An assessment of laboratory values and symptoms after initiation of psychotropic treatment is recommended.
Collins and Anderson, 2000¹⁶	Female	76	Hyponatremia SIADH	Recovery	Risperidone	The lack of confounding and risk factors led to the diagnosis of SIADH secondary to medication.	Monitoring of the electrolyte profile is especially important in elderly patients who are introduced to second-generation antipsychotic medications.
Akkaya et al, 2006¹⁷	Male	32	Hyponatremia Rhabdomyolysis	Recovery	Ziprasidone	The use of ziprasidone could have complicated the treatment of hyponatremia, leading to the development of rhabdomyolysis.	A possible relationship exists between hyponatremia and rhabdomyolysis, but in the context of antipsychotics, more research needs to be done.^{^a}
Nagasawa et al, 2014¹⁸	Male	20	Hyponatremia Water intoxication	Death	Olanzapine	Adverse effects are associated with high concentrations of olanzapine in the blood, and the high concentration was found in the postmortem report.	^{^a}
Lee et al, 2015¹⁹	Female	40	Hyponatremia SIADH	Recovery	Risperidone	The development of SIADH after treatment with risperidone was seen soon after the dosage was increased. However, SIADH was asymptomatic until the appearance of seizures.	Clinicians should regularly monitor serum electrolyte levels to detect SIADH in patients with schizophrenia who are taking risperidone.
Ogilvie and Croy, 1992²⁰	Female	39	Hyponatremia	Recovery	Clozapine	The event is associated with the use of clozapine because of the lack of other contributing factors.	Clinicians should be cautious and aware of the high occurrence of seizures with dosage exceeding 600 mg/day of clozapine.
Kohen et al, 2008²¹	Male	50	Hyponatremia SIADH	Recovery	Aripiprazole	Hyponatremia was induced by aripiprazole.	Clinicians should be cautious and aware of the hyponatremic-inducing effects of second-generation antipsychotics that may occur after initiation.
Lecamwasam and Alexander, 2011²²	Female	56	Hyponatremia	Recovery	Aripiprazole	Worsening psychosis and hyponatremia-related deteriorations were possibly confused.	Medical practitioners need to be aware of the similar symptoms of chronic psychosis and hyponatremia.
Whitten and Ruehter, 1997²³	Male	48	Hyponatremia Rhabdomyolysis	Recovery	Risperidone	The patient in good physical health developed hyponatremia 14 days after starting risperidone.	^{^a}

SIADH, syndrome of inappropriate antidiuretic hormone secretion.
↵^a A recommendation for clinicians was not provided.