If you're in UK, I recommend reading all these documents below UK B12 documents BSH Cobalamin and Folate Guidelines b-s-h.org.uk/guidelines/gui
B-complex injections combine several B vitamins that support adrenal function, metabolism, mood, and cellular energy
Also, The National Institutes of Health and the Institute of Medicine have determined that no adverse effects have been established from excess amounts of B-12 in the body
Glucose from Carbohydrate foods is used as a form of energy, so this is the reason why people with vitamin B-12 deficiencies experienced fatigue
seek care for any concerning symptoms
B12 and B complex injections are usually given as a one-time treatment or as part of a short-term treatment plan, rather than as a long-term supplementation strategy