Suppliers should ship with ice packs and provide storage instructions
In the withdrawal trial, continuing preserved loss far better than switching to placebo, which regained about 14% over a year. The metabolic benefit fades in proportion to the weight regained, so a taper plus protein and resistance training beats a hard stop
without enough B12, oxygen delivery drops, leaving you breathless and tired
Third, it has toxicological uses as an adjunct in lead and ethylene glycol poisoning and intravenous dosing can cause anaphylaxis, so the IM/SC route is preferred
B12 injections can be given in a variety of settings, including med spas, doctors offices, and even at home