side effects after b12 injection Best Shots in Chicago & Naperville 2026 What Does a B12 Shot

Cyanocobalamin (Vitamin B12)..............5000 mcg Benzyl Alcohol (preservative).................1.0% v/v Sodium Chloride.................................0.22% w/v Ammonium Sulfate...............................0.1% w/v Citric Acid..........................................0.01% w/v Sodium Citrate..................................0.008% w/v Inject subcutaneously or intramuscularly

This effect is complementary to the action on the GLP-1 receptor

Freezing can cause the vitamins (especially riboflavin and perhaps dexpanthenol) to precipitate or the solution to phase-separate

The Peptide Interaction Checker cross-references peptide combinations against documented interactions and side effect overlap