Make sure your patients who use insulin are aware of the following study results: 

Cold Can Affect Your Insulin:  Insulin Concentration in Vials Randomly Purchased in Pharmacies in the U.S. Can Lose Its Strength in the Cold Supply Chain

The insulin content in vials/cartridges should be 95 U/ml upon release. No independent confirmation of insulin concentration is available when purchased in the pharmacy (the end of the cold supply chain). The study quantitatively measured intact insulin in randomly acquired multidose human insulin vials by standard analytical methods. Eighteen 10 ml vials from two manufacturers (M1 and M2) were randomly acquired. The intact insulin concentration ranged from 13.9 to 94.2 U/ml, mean 40.2 U/ml. No vial met the minimum standard of 95 U/ml. These results imply the cold supply chain impacts insulin concentrations to a larger extent than anticipated. It is recommended that when starting a new container of insulin you check your blood sugars more frequently, J Diabetes Sci Technol. 2017 Dec 1:1932296817747292. doi: 10.1177/1932296817747292. [Epub ahead of print]