How much water is needed to mix with 31g of anti-flu powder to get 12mg/ml concentration?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: September 18, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Calculating Water Volume for Anti-Flu Powder Reconstitution

To achieve a concentration of 12 mg/ml from 31g of anti-flu powder, you need to add 2,583 ml (approximately 2.58 liters) of water.

Calculation Method

The calculation to determine the correct volume of water follows a straightforward concentration formula:

  1. First, convert the powder weight to milligrams:

    • 31g = 31,000 mg
  2. Apply the concentration formula:

    • Concentration = Amount of drug / Volume
    • 12 mg/ml = 31,000 mg / x ml
    • x = 31,000 mg ÷ 12 mg/ml
    • x = 2,583.33 ml

Verification

This calculation ensures that when 31g (31,000 mg) of the anti-flu powder is dissolved in 2,583 ml of water, the resulting solution will have the required concentration of 12 mg/ml.

Important Considerations

  • Measuring accuracy: Use a calibrated measuring device for precise water measurement.

  • Mixing technique: Ensure complete dissolution of the powder by:

    • Adding the powder to a portion of the required water
    • Stirring thoroughly until completely dissolved
    • Adding the remaining water to reach the final volume
    • Mixing again to ensure uniform concentration
  • Storage: Once reconstituted, follow the medication's specific storage instructions regarding:

    • Temperature requirements
    • Protection from light
    • Expiration timeline after reconstitution

Clinical Context

While the guidelines reviewed primarily discuss standard dosing for influenza medications 1, the principles of pharmaceutical preparation apply to all medications. Proper reconstitution ensures accurate dosing, which is critical for achieving therapeutic efficacy while minimizing the risk of adverse effects.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.