Methylcobalamin and Hydroxocobalamin are two forms of Vitamin B 12 that many patients use as an injection to improve their levels. Some pharmacies dispense B12 in syringes. Watch this video from The Compounding Center in Virginia to see why that's not a good idea with these preservative free drugs. Injections need to be kept in sterile, closed containers until use to avoid accidental bacterial or fungal contamination. A vial is best in this situation! Plus, it allows for dosing flexibility and affordability for your patients.