Vitamin B12 shot side effects Most people tolerate vitamin B12 injections well, but possible side effects include: Mild: soreness or redness at injection site, mild diarrhea, nausea, headache, itching Rare but serious: allergic reactions (rash, swelling, difficulty breathing), low potassium (hypokalemia), dizziness or heart rate changes Get emergency medical help if you have signs of an allergic reaction to Vitamin B12: hives
A comprehensive safety and tolerability study evaluated approximately 900 participants across six trials with the following protocols: Subcutaneous/Intravenous Protocols: Single doses ranging from 25 to 400 mcg/kg body weight were tested
Consider reducing dose to see if effects diminish
Vitamin B12 deficiency can also cause symptoms that affect the brain and nervous system (neurologic symptoms), including: Numbness Muscle weakness Mental health problems, ranging from mild depression or anxiety to confusion and dementia Balance and coordination issues Needles and pins Incontinence What is the best form of vitamin B12 to take
