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Is insulin diluted when stored in water?
Phillip Plager1, Kadiro Nurie2, Trevor Omann1
1University of Minnesota Masonic Children's Hospital, Minneapolis, MN, USA.
Pediatric Diabetes
|January 31, 2016
Summary
Storing insulin in water does not dilute it, even without replacing withdrawn insulin with air. This method may make insulin easier to draw, but bacterial contamination remains a concern.
Area of Science:
- Endocrinology
- Pharmaceutical Science
- Public Health
Background:
- Insulin storage presents challenges in resource-limited settings.
- Patients in Uganda were observed storing insulin vials submerged in water.
Purpose of the Study:
- To investigate if withdrawing insulin without replacing it with air creates a vacuum.
- To determine if this vacuum leads to water entering the vial and diluting the insulin.
Main Methods:
- Forty 10 mL insulin vials (NPH and regular) were used.
- Insulin was withdrawn; air was added back to half the vials.
- Vials were weighed, then half were submerged in water for 24 hours; all were re-weighed after 48 hours.
Main Results:
- No significant difference in weight change was observed between vials with or without added air after submersion.
- Further insulin withdrawal before submersion also showed no difference in weight change related to air addition.
Conclusions:
- Withdrawing insulin without adding air does not cause water to enter and dilute the insulin in submerged vials.
- This technique may facilitate insulin withdrawal but does not address potential bacterial contamination.
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