Question

As a home health nurse working with a newly diagnosed 17-year-old young man with schizophrenia who lives at home with his parents, you stop by to check on the patient at the request of his parents. The parents share their concerns that the patient’s medication, paliperidone (Invega), does not appear to be working as well as it had when the patient first started taking it. They report that the patient is more irritable; has an increase in his hallucinations with the patient talking aloud again in response to auditory hallucinations, frequently laughing at apparently nothing; has a firmly fixed delusion that he is inhabited by demons who are slowly eating his internal organs; and has increased consumption of water with the patient drinking large volumes of water in a way that his parents describe as, “He seems driven to drink. We’re not sure why. Perhaps he’s attempting to flush those demons out?” Upon entering the patient’s room, you notice a strong smell of urine. His parents are obviously embarrassed by this and quickly tell you they recently took the patient to his medical care provider to rule out a urinary tract infection. They tell you the urine analysis showed only a low specific gravity, and the only other abnormal laboratory finding was that his serum sodium level was found to be low. (Learning Objectives #1 & 6)

1. Given the presenting data, what do you expect is occurring with this patient? What laboratory data will confirm your suspicion?

Answer 1

The patient is suffering with psychologic polydypsia. It was occured as a side effect of antipsychiatric drug induced hyponatrenaemia. paliperidone which is an active metabolite of resperidone can cause hyponatrenaemia, which leads to polydypsia. The low sodium levels will confirm the suspicion. Due to polydypsia the patient is a produces more amount of urine.