Sodium Content of D5W vs D10W
Both D5W (5% dextrose in water) and D10W (10% dextrose in water) contain zero sodium (0 mEq/L). These solutions are dextrose dissolved in sterile water without any electrolytes.
Composition and Electrolyte Content
- D5W and D10W are sodium-free solutions that contain only dextrose and water, with no sodium or other electrolytes 1
- D5W contains 5 grams of dextrose per 100 mL, while D10W contains 10 grams of dextrose per 100 mL, but neither contains any sodium 2
- Both solutions are recommended for pediatric emergency departments as resuscitation medications specifically because they provide glucose without sodium 2
Clinical Implications of Zero Sodium Content
Effect on Serum Sodium
- D5W administration dilutes serum sodium concentration because it contains 0 mEq/L sodium compared to normal plasma sodium of 135-145 mEq/L 1
- D5W is the primary fluid recommended for free water replacement in patients with hypernatremia precisely because it lacks sodium 1
- When hyponatremia has been overcorrected too rapidly (>8 mmol/L in 24 hours), immediately switching to D5W can relower sodium levels to prevent osmotic demyelination syndrome 1
Comparison to Sodium-Containing Solutions
- Normal saline (0.9% NaCl) contains 154 mEq/L sodium, making it fundamentally different from D5W or D10W 1
- Changing drug diluents from D5W to saline significantly increases the incidence of hypernatremia (27.3% vs 14.6%) and hyperchloremia (36.9% vs 20.4%) 3
- In critically ill patients, drug diluents can account for 21.4% of total infusion volume, making the choice between sodium-free (D5W/D10W) and sodium-containing solutions clinically significant 3
Important Clinical Caveats
Tonicity After Metabolism
- D5W and D10W are isotonic when infused but become hypotonic once dextrose is metabolized by cells, providing no renal osmotic load after dextrose clearance 4
- After dextrose metabolism, the remaining free water distributes across intracellular and extracellular compartments, with approximately 80-100 mL per liter expanding plasma volume 4
When Sodium is Needed
- For maintenance fluid therapy in pediatric patients, isotonic solutions with appropriate potassium chloride and dextrose are recommended to decrease the risk of developing hyponatremia 5
- Commercial preparations of D5 with various sodium concentrations are available when both dextrose and sodium are clinically indicated 5
- Hypotonic solutions like D5W can worsen cerebral edema after closed head trauma, whereas isotonic saline does not 6