You should always opt for stocking up on pure and efficient methylcobalamin-based B12, making sure to read the ingredients label carefully for any hidden nasties, and reach for a daily dose that will meet your requirements, plus some to ensure absorption (2000mcg weeky for adults under 65 should do the job just fine!)
Common, mild side effects: Pain, redness, or itching at the injection site Mild nausea or diarrhea Headache Temporary dizziness Rare but more serious reactions: Allergic reactions (rash, swelling, breathing difficulty) Heart palpitations Low potassium levels during rapid correction of severe deficiency Very rare cases of anaphylaxis requiring emergency care Seek medical attention immediately if you experience symptoms of a serious allergic reaction
Retrieved from Lacombe, V., Chabrun, F., Lacout, C., Ghali, A., Capitain, O., Patsouris, A., et al
Cost impact of intrathecal polyanalgesia