still tired after b12 injections Feeling worse Injection: Answering concerns Why do I feel worse

Generally, its difficult to say precisely how long a vitamin B12 shot lasts in the body

People with digestive or absorption issues : As mentioned, conditions like Crohns disease, IBS, or celiac disease can prevent proper absorption of B12 making injections the best option for getting enough of the nutrient

This makes it useful for studying metabolic dysfunction and epigenetic control

Some people require more frequent injections and would usually be guided by specialist hospital colleagues

Injectable administration ensures rapid systemic absorption , particularly valuable for patients with malabsorption syndromes, gastrointestinal disorders, or those requiring higher therapeutic doses