The choice of solvent and the method of reconstitution are critical
Cyanocobalamin is indicated for vitamin B12 deficiencies due to malabsorption which may be associated with the following conditions: Addisonian (pernicious) anemia Gastrointestinal pathology, dysfunction, or surgery, including gluten enteropathy or sprue, small bowel bacteria overgrowth, total or partial gastrectomy Fish tapeworm infestation Malignancy of pancreas or bowel Folic acid deficiency It may be possible to treat the underlying disease by surgical correction of anatomic lesions leading to small bowel bacterial overgrowth, expulsion of fish tapeworm, discontinuation of drugs leading to vitamin malabsorption (see PRECAUTIONS-Drug Interactions), use of a gluten-free diet in nontropical sprue, or administration of antibiotics in tropical sprue

What your describing is not uncommon because methylation process is so complex & you may be deficient in other co-factors, such as B6, B2, Same, B12, etc Too much 5MTHF can drive overmethylation or dampen glutathione production and lead to agitation, irritability
What you should know
Copper peptides promote collagen and elastin production while ceramides ensure the skin barrier remains intact to retain these structural improvements