Since B12 shots are injected intramuscularly bypassing the digestive process, they start to work immediately. Typically, our patients experience positive effects between 24-72 hours after the treatment
Avoid alcohol for 48 hours after your treatment. Avoid strenuous exercise for 48 hours after your treatment. Avoid touching the injection site for 6 hours after your treatment. You may experience a dull ache at the injections site for around 1 hour after your treatment.