In preclinical tests, the most commonly noted side effect was mild local irritation at the injection site
Micronutrient Deficiencies in Morbidly Obese Women Prior to Bariatric Surgery
Typically, our patients experience positive effects between 24-72 hours after the treatment
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However, some patients receiving high-dose B12 supplementation or injections may experience adverse reactions, though these relate to the treatment rather than the elevated levels: Possible reactions to B12 supplementation (particularly injections): Skin reactions, including acneiform eruptions or rashes Pruritus (itching) Injection site reactions (with parenteral administration) Rare hypersensitivity reactions Non-specific symptoms such as headaches, dizziness, or gastrointestinal disturbances have been reported by some patients taking B12 supplements, but causality is not well established in clinical evidence
Understanding these recommendations helps prevent both deficiency and unnecessary over-supplementation
