Commonly reported issues include mild gastrointestinal discomfort, particularly when starting the compound, and temporary headaches during the adjustment period
A complete blood count (CBC) can also reveal megaloblastic anemia, a hallmark of B12 deficiency
As with all compounds in this category, findings remain within the scope of controlled laboratory research
Across the six published trials, the most common adverse events were headache, mild gastrointestinal effects (diarrhea, flatulence, nausea), nasopharyngitis, fatigue, dizziness, and mild injection-site reactions
In individuals with normal B12 metabolism and no ongoing deficiency, the body's stores can theoretically last several years
B12 injections have become one of the most widely marketed treatments at med spas across the United States, driven by consumer demand for quick energy boosts, anti-aging support, and metabolism enhancement