B 12 (Methylcobalamin) Therapy MedClub by Dr Jenn Dr. prescribed B12 injections. Pharmacy only gave me vials. Where do you get your needles and syringes? What size?? Where do I inject? : r B12_Deficiency VITAMIN B12 (Generic) Injectable Solution, 1000 mcg mL, 100 mL vial Easy Refills Chewy Rx Types of injections explained Intramuscular (IM) Inserted at 90 to deliver medication deep into the muscle, allowing relatively fast absorption due to rich blood supply. Subcutaneous (SC) Inserted at about 45 Cyanocobalamin (B12) Products American Regent What Happens If You Inject B12 Into Fat? PA Relief