Psychiatric Drugs and Hyponatremia

I have now been working in the emergency department for just under four months. I have learned so many amazing things. I am consistently overwhelmed by the wealth of knowledge I have the opportunity to absorb while here.

I also have noticed that there tends to be trends in the patients that you receive during a day or even a week. We joke that each nurse seems to get a “special of the day” where several different patients come in with similar chief complaints, presentations, or diagnoses.

Last week, my special of the day was psychiatric-medication induced hyponatremia. Oddly specific, huh? I thought so as well so I began to do some research.

For those in the medical field, we all know that psychiatric drugs can have some extensive effects on certain electrolytes, mainly sodium, calcium, and potassium. But it can affect others. And those drugs can also affect eating and drinking habits that can make the electrolyte imbalances more profound.

For those not in the medical field, now you know. Psychiatric medications can have significant effects on your electrolytes, *ESPECIALLY* your sodium. If you are on any type of psych med, you should be getting routine blood work done. If you are not getting routine blood work done, then you should be. It is also important to note that there are certain psych medications such as Lithium that do require routine lithium blood level testing but make sure they are doing metabolic screenings as well.

There are specifically a few drugs (valproic acid, vincristine, cyclophosphamide, amitriptyline, desipramine, and carbamazepine) that can trigger SIADH (Syndrome of Inappropriate Antidiuretic Hormone secretion). That means that the patient will retain water and won’t urinate nearly enough. That leads to kidney dysfunction and can lead to diluted sodium in the system, leading to hyponatremia.

The main presentation of hyponatremia is altered mental status. So if you or a loved one all of the sudden have some unusual mentation changes, that could be the root cause of it. It also can present as dizziness, nausea, confusion, fatigue, and headache. And it can be genuinely very serious and life threatening. If you are at home and suspect an imbalance, it is imperative that you call or doctor at the very least, but they will likely recommend you pay the emergency room a visit.

It is easily correctable if caught early with proper tapering of the medication and supportive drug therapy, but it must be done by a medical professional and may require temporary hospitalization.

But when in doubt, check it out. That’s what I always say. I hope this has given you the knowledge to ask your doctor for routine chemistry and has given you a deeper insight into potential signs and symptoms at home.

References:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3025989/