05-06-2017 02:00 PM
05-06-2017 02:10 PM
Yes, the vial is a single-dose vial and all of the drug should be used. The dating on the vial is for chemical stable but not microbial sterility. II is very confusing but we need to always remember what type of vial we are using. Hope this helps.
05-07-2017 01:39 PM
05-07-2017 09:45 PM
Since you have two concentration data points showing the same chemical stability, you can usually extrapolate and apply the same chemical stability. This concept is known as drug concentration bracketing. Penicillin is a molecule that you can apply this principle. I don't believe you have to change your current practice. If you are so inclined, you can read the attached FDA guidance of stability and bracketing. Hope this helps.