If you're unsure how long an opened vial has been at room temperature, refrigerate it immediately and mentally note the date you first opened it
It is important to note however, that not all forms of vitamin B12 are created equally
Dyck GJB, Raj P, Zieroth S, Dyck JRB, Ezekowitz JA
If appropriate, a licensed medical provider can review your symptoms, health history, and any relevant lab work to determine whether vitamin B12 support may be a suitable option for your needs
Be patient and realistic about the expected results, and communicate regularly with your healthcare provider about your progress
The conservative cutoff is the labeled date