Hi I bought the B12 injectable liquid but there's no use by date on it or how long you have to use it once it's opened. Anyone know the answer? TIA x Compounded Vitamin B Complex Injection Empower Pharmacy Full B 12 Injection: Uses, Side Effects, Price & Substitutes 5 Ways Lipotropic B12 Injections Help You In Weight Loss Vitamin B12 Injection Dose for Adults: 7 Essential Dosage Facts & Schedules Liv Hospital Normal B12 Levels (by Age) vs. the Optimal Range PA Relief