B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics Did you know long term use of PPIs like pantoprazole (Protonix) can cause: B12 deficiency hypomagnesemia calcium malabsorption which can lead to bone fx acute interstitial nephritis B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics B12 Shots & B12 Injections: The Good, Bad and Alternative! What Happens When You're Allergic to Vitamin B12