Dextrose, also known as D-glucose, is a sterile, nonpyrogenic solution used primarily for fluid replenishment, caloric supplementation, and the management of hypoglycemia. It may be administered orally or intravenously, depending on clinical necessity.Mechanism of Action
Glucose is the primary monosaccharide utilized by the body for energy. Each gram provides approximately 4 kcal (16.7 kJ). It is essential for cellular metabolism, especially in brain tissue, which relies heavily on glucose as an energy source.
When administered intravenously:
- Glucose rapidly enters systemic circulation.
- It is taken up by tissues and metabolized via glycolysis and the citric acid cycle, producing CO₂, water, and ATP.
- In the presence of insulin, glucose uptake by cells is enhanced.
- Co-administration with insulin drives potassium into cells, making it useful in treating hyperkalemia.
Pharmacokinetics
- Absorption: Immediate (IV route)
- Distribution: Throughout extracellular and intracellular compartments
- Metabolism: Primarily in the liver
- Excretion: As CO₂ (lungs) and water (urine)
- Max Utilization Rate: ~6 mg/kg/min in healthy individuals
Clinical Indications
- Hypoglycemia (acute symptomatic)
- Dehydration with caloric deficiency (e.g., vomiting, diarrhea, starvation)
- Intravenous nutrition (e.g., Total Parenteral Nutrition)
- Hyperkalemia (when co-administered with insulin)
- Ketosis or diabetic ketoacidosis (DKA) – as adjunctive therapy
- Osmotic agent in peritoneal dialysis
- Diluent for IV medications
- Diagnostic testing (e.g., glucose tolerance tests)
Dosage & Administration
General Guidelines
- The concentration and volume depend on age, weight, fluid/electrolyte status, and clinical indication.
- Concentrations range from 2.5% to 50%.
Adult Dosing
- Maintenance fluid/caloric supply: 500 mL to 3 L/day IV
- Hypoglycemia (acute): 25–50 mL of 50% dextrose IV push (D50W)
- Hyperkalemia: 10–25 g of glucose IV + 5–10 units of insulin
- Tissue dehydration (rare): 20–50 mL of D50W IV (transient effect)
Pediatric Dosing
- 0–10 kg: 100 mL/kg/day
- 10–20 kg: 1000 mL + 50 mL/kg for each kg >10
- >20 kg: 1500 mL + 20 mL/kg for each kg >20
Infusion rate must be individualized to avoid volume overload or hyperglycemia.
Special Clinical Uses
| Condition | Glucose Formulation | Notes |
|---|---|---|
| Hypoglycemia | Dextrose 50% IV push (D50W) | Fast-acting |
| Hyperkalemia | Dextrose + Insulin | Drives K⁺ intracellularly |
| Ketosis/DKA | Dextrose 5–25% | Reduces ketone production |
| Osmotic Diuresis | Dextrose 50% (less common use) | Short-lived |
| Peritoneal Dialysis | Dextrose 1.5%–4.25% solutions | Maintains osmotic gradient |
Adverse Effects
Common Side Effects
- Phlebitis (especially with high concentrations like D25/D50)
- Local irritation or tissue necrosis (if extravasation occurs)
- Hyperglycemia and glycosuria
- Electrolyte imbalance (e.g., hypokalemia, hyponatremia)
Serious Reactions
- Hyperosmolar hyperglycemic state (HHS)
- Hypoglycemia (rebound, especially with insulin use)
- Volume overload (particularly in cardiac or renal impairment)
- Pulmonary edema (with excessive infusion)
Contraindications
- Known hypersensitivity to dextrose
- Uncontrolled hyperglycemia
- Diabetic ketoacidosis without concurrent insulin therapy
- Intracranial or intraspinal hemorrhage (avoid hyperosmolar solutions)
Precautions
Use with Caution in:
- Patients with diabetes mellitus
- Heart failure, renal impairment, or hepatic insufficiency
- Patients on glucocorticoids or under severe stress
- Neonates and elderly, due to altered glucose metabolism
Pregnancy & Lactation
- Safe in pregnancy when used appropriately.
- High doses during labor may lead to neonatal hypoglycemia due to fetal hyperinsulinemia.
Pediatric and Geriatric Considerations
- Neonates: Risk of intracranial hemorrhage with hypertonic solutions.
- Elderly: Monitor for fluid overload and arrhythmias.
Drug Interactions
- No significant interactions with most drugs.
- Mild interactions:
- Magnesium salts (e.g., magnesium sulfate, citrate)
- Electrolyte shifts may occur when co-administered
High-Yield Clinical Pearls
- D50W is first-line treatment for severe symptomatic hypoglycemia.
- Monitor electrolytes, especially potassium and sodium, during prolonged infusion.
- In hyperkalemia, always co-administer insulin to facilitate intracellular K⁺ shift.
- For TPN, dextrose is balanced with amino acids, lipids, electrolytes, and vitamins.
- Use central lines for high concentrations (>10%) to avoid phlebitis.
