B12 injections can help to boost energy levels, reduce fatigue, and support muscle growth and recovery
Because this article focuses on Epitalon as a compound, dosage should only be mentioned briefly
Further, NICE and the BNF says that if there are neurological symptoms present, then every other day injections are the recommended treatment, so all the points you make about B12 being stored and sufficient are not really relevant
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In short: animals given BPC-157 heal Achilles tendons, muscle tears, ligament injuries, and even crushed bones dramatically faster and stronger than untreated animals