Important distinction: "Legal to compound" under 503A is NOT the same as "FDA approved." An FDA-approved drug has gone through full clinical trials and received a New Drug Application (NDA) approval
Gene Ther 2017;24:497
[16] Only small amounts of choline are synthesized by the human body, necessitating its intake from external sources
Systemic allergic reactions to the benzyl alcohol in bacteriostatic water are extremely rare, especially given the small amounts used, but as with any injection, if you were to develop symptoms like hives, difficulty breathing, or low blood pressure after an injection, seek medical care
For this reason, B12 injections are used to offset the many symptoms of vitamin B12 deficiency, such as fatigue and weakness, poor moods, and low concentration