While it's broadly deemed safe, some users may experience gastrointestinal upsets, occasional headaches, or skin irritations
Ice-crystal formation during each freeze-thaw cycle inflicts mechanical damage on molecular structure, and pre-splitting eliminates the cumulative loss that comes from thawing one vial multiple times
Other causes are conditions affecting the stomach or small intestine, such as Crohns disease, operations such as gastrostomies (which involve removal of part of the stomach), and certain medications
Two injections of the same drug at the same site don't qualify
Evidence on B12 and sleep is mixed: B12 helps regulate circadian rhythm in some contexts, yet high B12 status has been linked with shorter sleep in others
These new codes are listed in table 1