The correct syringe size determines how you measure and draw your dose accurately
Much of what patients read online reflects animal studies or anecdotal reports not established clinical efficacy in humans
Examples of these health conditions include those with a lack of stomach acid, those who have undergone bariatric surgery, anemia caused by the inability to absorb the vitamin, other autoimmune digestive diseases, as well as several medications
A B12 injection may be worth discussing if: You have absorption problems: Conditions like Crohn's disease, celiac disease, or atrophic gastritis can reduce how well your body absorbs B12 from food, and past gastric surgery can have a similar effect
Drug interaction guide Originally published 25 Jan 2026 DownloadDownload Share Language Discussion Audio Version Add to preferred sources on Google Taking high doses of Vitamin C at the same time as Vitamin B12 can reduce the amount of Vitamin B12 your body absorbs and uses
