can you take b12 tablets as well as injections How Often I Injections? Vitamin B12 injections vs tablets:

Nausea High doses of vitamin b1, b6, and b12 injection may lead to the inclination like nausea where person face vomiting issue

In contrast, there is some evidence of an enhancement of the maximum absorption via intrinsic factor, by up to a factor of 2, when the vitamin B12 is accompanied by food, but this is not consistently observed and probably only applies when the food quantity and vitamin B12 dose are sufficient to slow the passage of the vitamin B12 through the small intestine enough (about three hours or more) to allow each intrinsic factor receptor to absorb two molecules of vitamin B12 from the oral dose rather than one

[16] Although cyanocobalamin lacks a defined upper-toxicity threshold due to its water solubility and renal elimination, exceptionally high cumulative doses have been temporally associated with acneiform eruptions, altered potassium homeostasis, and theoretical thrombotic risk, emphasizing the importance of evidence-based dosing

This effect supports research exploring cellular energy dynamics, endurance enhancement, and overall mitochondrial efficiency within metabolic health models