Why Do I Feel Worse After My B12 Injection? Understanding Post Injecti Oxford Origins Feeling worse after B12 Injection: Answering concerns. La Vie Med Spa Exhausted after shot day : r Zepbound Feeling exhausted, run down, foggy or low this winter? Cold weather, darker days and busy schedules can drain your energy fast and that's where a B12 injection can make all the difference Why Do I Feel Worse After My B12 Injection? Causes & Management Bolt Pharmacy Feeling exhausted no matter how much you sleep? Vitamin B12 deficiency is more common than people think affecting up to 15% of people. Treatment may include oral supplements or B12 injections. Save