**5.3 Additional considerations for antipsychotics and hyponatremia**

Antipsychotic medications alone have been reported in the literature to be associated with hyponatremia; however, recently, the long-acting risperidone injectable treatment has been implicated in hyponatremia as well. In this case, the patient did not improve simply with the removal of risperidone, due to the extended half-life, and ultimately required Tolvaptan administration [17]. The half-life of these medications may be an important factor in determining the management of subsequent hyponatremia. Along a similar vein, Fabrazzo et al. [16] detail that hyponatremia and other electrolyte derangements are often only detected in patients with psychiatric diagnoses when they are hospitalized. This is a critical consideration for clinicians in terms of practice, particularly whether there is an impetus for psychiatrists

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*Hyponatremia and Psychiatric Diseases DOI: http://dx.doi.org/10.5772/intechopen.90011*

**5.4 Practice considerations**

**6.1 Alcohol and hyponatremia**

course, ultimately consuming more alcohol.

disorder.

to consider routinely monitoring electrolytes of patients on longstanding medications with the potential for these derangements, especially in patients with bipolar

There currently are no routine guidelines for screening of electrolyte abnormalities among patients with psychiatric diagnoses and this should be further evaluated given the range of dangerous consequences of hyponatremia, including seizure, as

**6. Alcohol and other substance use disorders affecting serum sodium**

**6.2 MDMA (3,4-methylenedioxymethamphetamine) and hyponatremia**

Stimulant use disorder in DSM-5 [1] is defined as a pattern of stimulant use within the past 12 months that has led to significant impairment in one's life characterized by at least two of the following including the stimulant is taken in larger amounts, persistent desire to cut down, increased time obtaining the stimulant, cravings, continued use despite recurrent impairment in social functioning, developed tolerance, and withdrawal symptoms present when stimulant use is ceased. MDMA (3,4-methylenedioxymethamphetamine), a stimulant, is thought to be associated with hyponatremia because of increased diaphoresis, yielding sodium loss, and compensatory water intoxication. It is not a common side effect of MDMA use; however, Armitage et al. [19] presented a case report of an 18-year-old woman who had a generalized tonic-clonic seizure in the setting of hyponatremia from MDMA intoxication. This woman's serum sodium was 121, notably close to what many would argue is severe hyponatremia. Notably, MDMA related hyponatremia with seizure is more common among young women under 30 years of age, particularly because of estrogen inhibiting the Na+-K+-ATPase. This ultimately inhibits

Substance use is also implicated in derangements of serum sodium, particularly among patients who abuse alcohol and MDMA. As defined by DSM 5 [1], alcohol use disorder is a pattern of alcohol use within the past 12 months that has led to significant impairment in one's life characterized by at least two of the following including alcohol taken in larger amounts, persistent desire to cut down, increased time obtaining alcohol, cravings, continued use despite recurrent impairment in social functioning, developed tolerance, and withdrawal symptoms present when alcohol use is ceased. As delineated in previous sections, there are profound potential consequences of hyponatremia, particularly because of sodium's role in maintaining nerve impulse conduction and neuromuscular excitability. Michal et al. [18] observed that in patients with likely alcohol use disorder, the level of derangement in serum sodium was associated with the worsening of physical and psychological quality of life; that is to say, patients with severe hyponatremia (<120 mmol/L) were likely to have worse quality of life than patients with low hyponatremia (<135 mmol/L) [18]. The specific causal pathways are not delineated; however, beer potomania is an observed phenomenon in which dietary insufficiency of protein, coupled with dietary sodium results in a sort of dilutional hyponatremia. It is possible that patients with more severe hyponatremia may be further in their disease

demonstrated in at least one of the cases delineated above [15].

**Figure 1.** *Plasma sodium levels over time.*

to consider routinely monitoring electrolytes of patients on longstanding medications with the potential for these derangements, especially in patients with bipolar disorder.
