1/2NS
Medical abbreviation · Pharmacy
| Stands for | Half-normal saline |
|---|---|
| Categories | Medical |
1/2NS stands for Half-normal saline, a pharmacy abbreviation.
Hypotonic IV fluid containing 0.45% sodium chloride (77 mEq/L of sodium), used to provide free water and maintenance fluid, for example in hypernatremia or in some diabetic ketoacidosis protocols once circulation is restored.
Example: Change IVF to 1/2NS at 150 mL/h once the corrected sodium is normal.
Usage notes
Also written 0.45NS, 0.45% NaCl or "half NS". Because it is hypotonic, it should not be used to resuscitate shock or in patients at risk of brain swelling. Mixing it with 5% dextrose gives D5 1/2NS. Hospital-acquired hyponatremia linked to hypotonic fluids has shifted practice toward isotonic maintenance fluids.
Related abbreviations
More pharmacy abbreviations
- AB – Therapeutically equivalent rating (Orange Book code)
- ADC – Automated dispensing cabinet
- ADF – Abuse-deterrent formulation
- AHFS – American Hospital Formulary Service
- amp – Ampule
- ANDA – Abbreviated New Drug Application
- APhA – American Pharmacists Association
- API – Active pharmaceutical ingredient
- aq – Aqueous
- ARCOS – Automation of Reports and Consolidated Orders System
- ASHP – American Society of Health-System Pharmacists
- AWP – Average wholesale price
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This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.