When B12 levels are low, the signs can be varied: Anemia: fatigue, weakness, pale skin, and dizziness Fatigue: a deep-seated weariness that doesn't improve with rest Nerve Damage: tingling or numbness in hands and feet, balance problems, and memory loss (seek medical advice promptly) Mood Disturbances: depression, irritability, and personality changes While our bodies can store B12 for years, some groups are more susceptible to deficiency, often because of absorption issues rather than diet
However, after a pen is opened or the vial is first used, the 30-day window begins, whether stored cold or warm
Gao H, Jiang Y, Zeng G, Huda N., Thoudam T., Yang Z., et al
The IRS standard requires your medical condition to be recorded in your chart, ideally with an ICD diagnosis code
doi:10.3390/biom10091211 Hunter CM, Figueiro MG