Other than these, if you are recommended for the consumption of supplements by your doctor to improve your deficiency of vitamin B12 are Methylcobalamin (Safest to consume) and Adenosylcobalamin
You might be a good candidate if you have confirmed low B12 levels (from lab work), follow a strict vegan/vegetarian diet, have digestive issues reducing B12 absorption (e.g., after gastric surgery, or with conditions like Crohns), or experience chronic fatigue and other symptoms linked to B12 deficiency
Consider magnesium glycinate if you tend to experience diarrhea, or magnesium citrate if you tend to be more constipated
[13] Sublingual or oral spray formulations are popular alternatives, though evidence does not show they are significantly more effective than standard tablets for most people with normal absorption
To ensure sufficient intake of vitamin B12, older individuals are recommended to obtain it from supplements or fortified foods, such as ready-to-eat breakfast cereals