Summary
Definition
History and exam
Key diagnostic factors
- medical history of psychiatric disorder or neurodevelopmental disorder
- water-seeking and drinking
Other diagnostic factors
- agitation
- polyuria
- headache
- nausea or vomiting
- lethargy or confusion
- seizures, delirium, or coma
Risk factors
- psychiatric disorders
- neurodevelopmental disorders
- smoking
- alcohol abuse
Diagnostic tests
1st tests to order
- plasma osmolality
- urine osmolality
- urine sodium
- serum sodium
- 24-hour urine volume
- urinalysis
- serum BUN
- water restriction test
Tests to consider
- vasopressin test
- plasma antidiuretic hormone
Treatment algorithm
severe hyponatremia (<125 mEq/L) or with neurologic symptoms
hyponatremia (125-130 mEq/L) or with GI symptoms
chronic polydipsia
Contributors
Authors
Shilpa Srinivasan, MD, DFAPA, DFAAGP
Vice Chair, Medical Staff Affairs, Behavioral Health Midlands, Prisma Health
Professor of Clinical Psychiatry
Program Director: Geriatric Psychiatry Fellowship
Director: Psychiatry Acting Internship and M4 Clerkship
Department of Neuropsychiatry and Behavioral Science
Prisma Health - University of South Carolina School of Medicine Columbia
Columbia
SC
Disclosures
SS is a board member of the American Association for Geriatric Psychiatry and serves on the Geriatric Psychiatry Exam Committee for the American Board of Psychiatry and Neurology.
Meera Narasimhan, MD, DFAPA
Professor and Chair
Department of Neuropsychiatry and Behavioral Science
Senior Medical Director
Prisma Health
Special Advisor to University of South Carolina President
Health Innovations and Economic Development
University of South Carolina School of Medicine Columbia
Columbia
SC
Disclosures
MN is a member of an advisory board for Alkermes.
Acknowledgements
Dr Shilpa Srinivasan and Dr Meera Narasimhan would like to gratefully acknowledge Dr Emily Williams and Dr Brian Dundas, previous contributors to this topic.
Disclosures
EW declares that she has no competing interests. BD is an author of one of the references for this topic.
Peer reviewers
Branimir Margetić, MD
Neuropsychiatric Hospital "Dr Ivan Barbot"
Popovaca
Croatia
Disclosures
BM is an author of a reference cited in this topic.
Aaron Pinkhasov, MD, DFAPA, FACLP
Chairman
Department Of Psychiatry
NYU Langone Hospital
Professor of Psychiatry and Medicine
NYU Long Island School of Medicine
Long Island
NY
Disclosures
AP declares that he has no competing interests.
Richard C Millson, MD, DTM&H, FRCPC
Associate Professor of Psychiatry
Queen's University
Kingston
Ontario
Canada
Disclosures
RCM declares that he has no competing interests. He is the author of some of the references cited in this topic.
Differentials
- Diabetes insipidus
- Diuretics
- Cerebral salt wasting
More DifferentialsPatient information
Heart failure
Psychogenic polydipsia
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