Can I mix Multivitamin (MVI) in Dextrose Normal Saline (DNS)?

Can You Mix Multivitamin (MVI) in Dextrose Normal Saline (DNS)?

Yes, you can mix multivitamins in dextrose normal saline, but this practice requires strict adherence to compatibility and stability data, and should ideally be done immediately before infusion to minimize vitamin degradation.

Key Principles for MVI Addition to IV Solutions

Timing of Addition

• Vitamins should be added immediately before infusion according to validated stability and compatibility data, as this minimizes degradation of essential elements 1.
• If immediate addition is not feasible, vitamins may be added by the end of the infusion cycle or as a bolus to prevent incompatibilities and degradation 1.
• The addition must be performed in aseptic conditions by appropriately trained personnel 1.

Critical Stability Concerns

• Ascorbic acid (vitamin C) and folic acid are highly unstable in IV solutions, with half-lives of only 1.1-8.9 hours for ascorbic acid and 2.7-24 hours for folic acid depending on storage conditions 2.
• Approximately 50% of total ascorbic acid degrades within 24 hours even under optimal conditions (refrigerated, protected from light) 3.
• Light exposure dramatically accelerates vitamin degradation—storage at room temperature with daylight exposure reduces ascorbic acid half-life to just 1.1 hours 2.

Compatibility Requirements

• You must have specific pharmaceutical data documenting compatibility and stability for the exact combination you plan to use 1.
• Electrolytes in dextrose normal saline (particularly calcium and phosphate) are prone to incompatibilities and precipitations that can destabilize vitamin preparations 1.
• Multi-valent cations can interact with vitamins, leading to degradation or precipitation 1.

Practical Administration Guidelines

Preferred Methods

• Add vitamins to lipid emulsions when available rather than dextrose solutions, as this increases vitamin stability and reduces losses, particularly for fat-soluble vitamins like vitamin A 4, 5.
• For patients receiving additional IV fluids beyond parenteral nutrition, adding multivitamins to isotonic saline solution is advisable 2.
• Consider administering vitamins as a separate bolus infusion rather than mixing with maintenance fluids to ensure complete delivery and avoid stability issues 1.

Storage and Handling

• If vitamins must be pre-mixed, store the solution at 2-8°C protected from light, and use within 24 hours 2, 3.
• Never store vitamin-containing solutions at room temperature or expose to daylight 2.
• The hanging time for any vitamin-containing admixture should not exceed 24 hours 1.

Important Caveats and Pitfalls

What NOT to Do

• Never extrapolate stability data from single-vitamin studies to multivitamin preparations, as mutual vitamin interactions significantly affect stability 2.
• Avoid routine pre-mixing of vitamins into IV solutions for prolonged storage, as this leads to unacceptable degradation of water-soluble vitamins 2.
• Do not assume that different brands of multivitamin preparations have identical stability profiles—the specific product matters 2.

Risk Mitigation

• Adding supplements to multi-chamber bags on hospital wards has been associated with increased bloodstream infection risk in one retrospective study, though this finding was not confirmed in other studies 1.
• Always use aseptic technique, preferably in a laminar flow cabinet, when adding vitamins to IV solutions 1.
• Document the exact composition, mixing time, and expiration time on the solution label 1.

Alternative Approaches

• Consider reducing MVI frequency rather than compromising stability: One study demonstrated that patients receiving home parenteral nutrition with MVI three times per week instead of daily showed no clinical manifestations of vitamin deficiency over 6 months 6.
• For patients requiring guaranteed vitamin delivery without stability concerns, separate vitamin administration (oral when possible, or IV bolus) may be preferable to mixing with maintenance fluids 2.

Bottom Line

While technically feasible, mixing MVI in DNS is suboptimal due to rapid vitamin degradation. If you must mix vitamins in dextrose normal saline, add them immediately before infusion, protect from light, use within 24 hours, and ensure you have specific compatibility data for your exact formulation 1, 2, 3.